diff --git a/Content.Server/FloofStation/InteractionVerbs/Actions/ToggleLayersAction.cs b/Content.Server/FloofStation/InteractionVerbs/Actions/ToggleLayersAction.cs
new file mode 100644
index 00000000000..bd80cd52436
--- /dev/null
+++ b/Content.Server/FloofStation/InteractionVerbs/Actions/ToggleLayersAction.cs
@@ -0,0 +1,47 @@
+using Content.Server.Humanoid;
+using Content.Shared.Humanoid;
+using Content.Shared.Humanoid.Markings;
+using Content.Shared.InteractionVerbs;
+
+namespace Content.Server.FloofStation.InteractionVerbs.Actions;
+
+/// <summary>
+///     Toggles a humanoid visual layer.
+/// </summary>
+[Serializable]
+public sealed partial class ToggleLayersAction : InteractionAction
+{
+    [DataField]
+    public HumanoidVisualLayers? NeededMarkingCategory;
+
+    [DataField]
+    public HashSet<HumanoidVisualLayers> ToggleLayers;
+
+    public override bool CanPerform(InteractionArgs args, InteractionVerbPrototype proto, bool isBefore, VerbDependencies deps)
+    {
+        if (NeededMarkingCategory == null)
+            return true;
+
+        var markingCategory = MarkingCategoriesConversion.FromHumanoidVisualLayers(NeededMarkingCategory.Value);
+
+        return deps.EntMan.TryGetComponent(args.Target, out HumanoidAppearanceComponent? bodyAppearance)
+           && bodyAppearance.MarkingSet.Markings.TryGetValue(markingCategory, out var markingList)
+           && markingList.Count > 0; // Check if at least one entry exists
+    }
+
+    public override bool Perform(InteractionArgs args, InteractionVerbPrototype proto, VerbDependencies deps)
+    {
+        if (deps.EntMan.TryGetComponent<HumanoidAppearanceComponent>(args.Target, out var humanoidAppearance))
+        {
+            foreach (HumanoidVisualLayers layer in ToggleLayers)
+            {
+                deps.EntMan.System<HumanoidAppearanceSystem>().SetLayerVisibility(
+                    args.Target,
+                    layer, humanoidAppearance.HiddenLayers.Contains(layer)
+                );
+            }
+        }
+
+        return true;
+    }
+}
diff --git a/Content.Shared/Floofstation/InteractionVerbs/Requirements/ClothingSlotBlacklistRequirement.cs b/Content.Shared/Floofstation/InteractionVerbs/Requirements/ClothingSlotBlacklistRequirement.cs
new file mode 100644
index 00000000000..befc4e35174
--- /dev/null
+++ b/Content.Shared/Floofstation/InteractionVerbs/Requirements/ClothingSlotBlacklistRequirement.cs
@@ -0,0 +1,20 @@
+using Content.Shared.InteractionVerbs;
+using Content.Shared.Inventory;
+using Robust.Shared.Serialization;
+
+namespace Content.Shared.Floofstation.InteractionVerbs.Requirements;
+
+
+/// <summary>
+///     Requires a mob to not be wearing anything in this slot.
+/// </summary>
+[Serializable, NetSerializable]
+public sealed partial class ClothingSlotBlacklistRequirement : InvertableInteractionRequirement
+{
+    [DataField] public string Slot;
+
+    public override bool IsMet(InteractionArgs args, InteractionVerbPrototype proto, InteractionAction.VerbDependencies deps)
+    {
+        return !deps.EntMan.System<InventorySystem>().TryGetSlotEntity(args.Target, Slot, out _);
+    }
+}
diff --git a/Content.Shared/Humanoid/HumanoidVisualLayers.cs b/Content.Shared/Humanoid/HumanoidVisualLayers.cs
index 8a2353d270e..3aa3f767057 100644
--- a/Content.Shared/Humanoid/HumanoidVisualLayers.cs
+++ b/Content.Shared/Humanoid/HumanoidVisualLayers.cs
@@ -11,6 +11,8 @@ public enum HumanoidVisualLayers : byte
         Hair,
         FacialHair,
         Chest,
+        Underwear, // Floof, add underwear
+        Undershirt, // Floof, add underwear
         Head,
         Snout,
         HeadSide, // side parts (i.e., frills)
diff --git a/Content.Shared/Humanoid/Markings/MarkingCategories.cs b/Content.Shared/Humanoid/Markings/MarkingCategories.cs
index 324c5463823..9e71da6764f 100644
--- a/Content.Shared/Humanoid/Markings/MarkingCategories.cs
+++ b/Content.Shared/Humanoid/Markings/MarkingCategories.cs
@@ -12,6 +12,8 @@ public enum MarkingCategories : byte
         HeadSide,
         Snout,
         Chest,
+        Underwear, // Floof, add underwear
+        Undershirt, // Floof, add underwear
         RightArm,
         RightHand,
         LeftArm,
@@ -38,6 +40,8 @@ public static MarkingCategories FromHumanoidVisualLayers(HumanoidVisualLayers la
                 HumanoidVisualLayers.HeadSide => MarkingCategories.HeadSide,
                 HumanoidVisualLayers.Snout => MarkingCategories.Snout,
                 HumanoidVisualLayers.Chest => MarkingCategories.Chest,
+                HumanoidVisualLayers.Underwear => MarkingCategories.Underwear, // Floof, add underwear
+                HumanoidVisualLayers.Undershirt => MarkingCategories.Undershirt, // Floof, add underwear
                 HumanoidVisualLayers.RArm => MarkingCategories.RightArm,
                 HumanoidVisualLayers.LArm => MarkingCategories.LeftArm,
                 HumanoidVisualLayers.RHand => MarkingCategories.RightHand,
diff --git a/Resources/Locale/en-US/Floof/interaction/verbs/underwear.ftl b/Resources/Locale/en-US/Floof/interaction/verbs/underwear.ftl
new file mode 100644
index 00000000000..819ef8eb96b
--- /dev/null
+++ b/Resources/Locale/en-US/Floof/interaction/verbs/underwear.ftl
@@ -0,0 +1,19 @@
+interaction-ToggleUndershirt-name = Toggle undershirt
+interaction-ToggleUndershirt-description = Toggle the undershirt of this person!
+
+interaction-ToggleUndershirt-success-self-popup = You toggle {THE($target)}'s undershirt.
+interaction-ToggleUndershirt-success-target-popup = {THE($user)} toggles your undershirt!
+interaction-ToggleUndershirt-fail-self-popup = You fail to toggle the undershirt.
+
+interaction-ToggleUndershirt-delayed-self-popup = You try to toggle {THE($target)}'s undershirt.
+interaction-ToggleUndershirt-delayed-target-popup = {THE($user)} is trying to toggle your undershirt!
+
+interaction-ToggleUnderwear-name = Toggle underwear
+interaction-ToggleUnderwear-description = Toggle the underwear of this person!
+
+interaction-ToggleUnderwear-success-self-popup = You toggle {THE($target)}'s underwear.
+interaction-ToggleUnderwear-success-target-popup = {THE($user)} toggles your underwear!
+interaction-ToggleUnderwear-fail-self-popup = You fail to toggle the underwear.
+
+interaction-ToggleUnderwear-delayed-self-popup = You try to toggle {THE($target)}'s underwear.
+interaction-ToggleUnderwear-delayed-target-popup = {THE($user)} is trying to toggle your underwear!
diff --git a/Resources/Locale/en-US/Floof/markings/underwear.ftl b/Resources/Locale/en-US/Floof/markings/underwear.ftl
new file mode 100644
index 00000000000..2caf959e76e
--- /dev/null
+++ b/Resources/Locale/en-US/Floof/markings/underwear.ftl
@@ -0,0 +1,41 @@
+markings-category-Undershirt = Undershirt
+markings-category-Underwear = Underwear
+
+marking-UndershirtStandard = Undershirt (Standard)
+marking-UndershirtStandard-t_undershirt = Undershirt
+
+marking-UndershirtSleeveless = Undershirt (Sleeveless)
+marking-UndershirtSleeveless-t_undershirt_sleeveless = Undershirt
+
+marking-UndershirtRolled = Undershirt (Rolled)
+marking-UndershirtRolled-t_rolled_undershirt = Undershirt
+
+marking-UndershirtRolledSleeveless = Undershirt (Sleeveless Rolled)
+marking-UndershirtRolledSleeveless-t_rolled_undershirt_sleeveless = Undershirt
+
+marking-UndershirtLong = Undershirt (Long)
+marking-UndershirtLong-t_long_undershirt = Undershirt
+
+marking-UndershirtClassic = Bra (Classic)
+marking-UndershirtClassic-snow_classic = Bra
+
+marking-UndershirtSports = Bra (Sport)
+marking-UndershirtSports-snow_sports = Bra
+
+marking-UndershirtStrapless = Bra (Strapless)
+marking-UndershirtStrapless-snow_strapless = Bra
+
+marking-UnderwearBoxers = Boxers
+marking-UnderwearBoxers-snow_boxers = Boxers
+
+marking-UnderwearBriefs = Briefs
+marking-UnderwearBriefs-snow_briefs = Briefs
+
+marking-UnderwearLowriders = Lowrides
+marking-UnderwearLowriders-snow_lowriders = Lowrides
+
+marking-UnderwearSatin = Satin
+marking-UnderwearSatin-snow_satin = Satin
+
+marking-UnderwearTanga = Tanga
+marking-UnderwearTanga-snow_tanga = Tanga
diff --git a/Resources/Prototypes/DeltaV/Entities/Mobs/Species/rodentia.yml b/Resources/Prototypes/DeltaV/Entities/Mobs/Species/rodentia.yml
index b82d6cad014..577d7b78d93 100644
--- a/Resources/Prototypes/DeltaV/Entities/Mobs/Species/rodentia.yml
+++ b/Resources/Prototypes/DeltaV/Entities/Mobs/Species/rodentia.yml
@@ -42,6 +42,8 @@
       - map: [ "enum.HumanoidVisualLayers.LArm" ]
       - map: [ "enum.HumanoidVisualLayers.RLeg" ]
       - map: [ "enum.HumanoidVisualLayers.LLeg" ]
+      - map: [ "enum.HumanoidVisualLayers.Underwear" ]
+      - map: [ "enum.HumanoidVisualLayers.Undershirt" ]
       - map: [ "jumpsuit" ]
       - map: [ "enum.HumanoidVisualLayers.LHand" ]
       - map: [ "enum.HumanoidVisualLayers.RHand" ]
diff --git a/Resources/Prototypes/DeltaV/Entities/Mobs/Species/vulpkanin.yml b/Resources/Prototypes/DeltaV/Entities/Mobs/Species/vulpkanin.yml
index 51641dd0182..d4278a44819 100644
--- a/Resources/Prototypes/DeltaV/Entities/Mobs/Species/vulpkanin.yml
+++ b/Resources/Prototypes/DeltaV/Entities/Mobs/Species/vulpkanin.yml
@@ -33,6 +33,8 @@
       - map: [ "enum.HumanoidVisualLayers.LArm" ]
       - map: [ "enum.HumanoidVisualLayers.RLeg" ]
       - map: [ "enum.HumanoidVisualLayers.LLeg" ]
+      - map: [ "enum.HumanoidVisualLayers.Underwear" ]
+      - map: [ "enum.HumanoidVisualLayers.Undershirt" ]
       - map: [ "jumpsuit" ]
       - map: [ "enum.HumanoidVisualLayers.LHand" ]
       - map: [ "enum.HumanoidVisualLayers.RHand" ]
diff --git a/Resources/Prototypes/DeltaV/Species/rodentia.yml b/Resources/Prototypes/DeltaV/Species/rodentia.yml
index 57c9cd89346..b7caa49cfbd 100644
--- a/Resources/Prototypes/DeltaV/Species/rodentia.yml
+++ b/Resources/Prototypes/DeltaV/Species/rodentia.yml
@@ -28,6 +28,8 @@
     FacialHair: MobHumanoidAnyMarking
     Snout: MobHumanoidAnyMarking
     Chest: MobRodentiaTorso
+    Underwear: MobHumanoidAnyMarking
+    Undershirt: MobHumanoidAnyMarking
     HeadTop: MobHumanoidAnyMarking
     HeadSide: MobHumanoidAnyMarking
     Tail: MobHumanoidAnyMarking
@@ -45,6 +47,13 @@
 - type: markingPoints
   id: MobRodentiaMarkingLimits
   points:
+    Underwear:
+      points: 1
+      required: true
+      defaultMarkings: [ UnderwearBoxers ]
+    Undershirt:
+      points: 1
+      required: false
     Hair:
       points: 1
       required: false
diff --git a/Resources/Prototypes/DeltaV/Species/vulpkanin.yml b/Resources/Prototypes/DeltaV/Species/vulpkanin.yml
index 520485ba9d4..9b4c356770f 100644
--- a/Resources/Prototypes/DeltaV/Species/vulpkanin.yml
+++ b/Resources/Prototypes/DeltaV/Species/vulpkanin.yml
@@ -21,6 +21,8 @@
     FacialHair: MobHumanoidAnyMarking
     Snout: MobHumanoidAnyMarking
     Chest: MobVulpkaninTorso
+    Underwear: MobHumanoidAnyMarking
+    Undershirt: MobHumanoidAnyMarking
     HeadTop: MobHumanoidAnyMarking
     HeadSide: MobHumanoidAnyMarking
     Tail: MobHumanoidAnyMarking
@@ -38,6 +40,13 @@
 - type: markingPoints
   id: MobVulpkaninMarkingLimits
   points:
+    Underwear:
+      points: 1
+      required: true
+      defaultMarkings: [ UnderwearBoxers ]
+    Undershirt:
+      points: 1
+      required: false
     Hair:
       points: 1
       required: false
diff --git a/Resources/Prototypes/Entities/Mobs/Species/arachne.yml b/Resources/Prototypes/Entities/Mobs/Species/arachne.yml
index ab4fba96311..fa8d6550f5f 100644
--- a/Resources/Prototypes/Entities/Mobs/Species/arachne.yml
+++ b/Resources/Prototypes/Entities/Mobs/Species/arachne.yml
@@ -34,6 +34,8 @@
       color: "#e8b59b"
       sprite: Mobs/Species/Human/parts.rsi
       state: l_arm
+    - map: [ "enum.HumanoidVisualLayers.Underwear" ] # Floof, add underwear
+    - map: [ "enum.HumanoidVisualLayers.Undershirt" ] # Floof, add underwear
     - map: [ "jumpsuit" ]
     - map: [ "enum.HumanoidVisualLayers.LHand" ]
       color: "#e8b59b"
diff --git a/Resources/Prototypes/Entities/Mobs/Species/arachnid.yml b/Resources/Prototypes/Entities/Mobs/Species/arachnid.yml
index e357f573f1e..7153fa8842a 100644
--- a/Resources/Prototypes/Entities/Mobs/Species/arachnid.yml
+++ b/Resources/Prototypes/Entities/Mobs/Species/arachnid.yml
@@ -92,6 +92,8 @@
       - map: [ "enum.HumanoidVisualLayers.LArm" ]
       - map: [ "enum.HumanoidVisualLayers.RLeg" ]
       - map: [ "enum.HumanoidVisualLayers.LLeg" ]
+      - map: [ "enum.HumanoidVisualLayers.Underwear" ] # Floof, add underwear
+      - map: [ "enum.HumanoidVisualLayers.Undershirt" ] # Floof, add underwear
       - map: ["jumpsuit"]
       - map: ["enum.HumanoidVisualLayers.LFoot"]
       - map: ["enum.HumanoidVisualLayers.RFoot"]
diff --git a/Resources/Prototypes/Entities/Mobs/Species/base.yml b/Resources/Prototypes/Entities/Mobs/Species/base.yml
index 02d3355b325..95b9cd7309d 100644
--- a/Resources/Prototypes/Entities/Mobs/Species/base.yml
+++ b/Resources/Prototypes/Entities/Mobs/Species/base.yml
@@ -17,6 +17,8 @@
     - map: [ "enum.HumanoidVisualLayers.LArm" ]
     - map: [ "enum.HumanoidVisualLayers.RLeg" ]
     - map: [ "enum.HumanoidVisualLayers.LLeg" ]
+    - map: [ "enum.HumanoidVisualLayers.Underwear" ] # Floof, add underwear
+    - map: [ "enum.HumanoidVisualLayers.Undershirt" ] # Floof, add underwear
     - map: ["jumpsuit"]
     - map: ["enum.HumanoidVisualLayers.LFoot"]
     - map: ["enum.HumanoidVisualLayers.RFoot"]
@@ -349,6 +351,8 @@
     - map: [ "enum.HumanoidVisualLayers.LArm" ]
     - map: [ "enum.HumanoidVisualLayers.RLeg" ]
     - map: [ "enum.HumanoidVisualLayers.LLeg" ]
+    - map: ["enum.HumanoidVisualLayers.Undershirt"] # Floof, add underwear
+    - map: ["enum.HumanoidVisualLayers.Underwear"] # Floof, add underwear
     - shader: StencilClear
       sprite: Mobs/Species/Human/parts.rsi
       state: l_leg
diff --git a/Resources/Prototypes/Entities/Mobs/Species/harpy.yml b/Resources/Prototypes/Entities/Mobs/Species/harpy.yml
index b3fcd565c4b..2105586b0f0 100644
--- a/Resources/Prototypes/Entities/Mobs/Species/harpy.yml
+++ b/Resources/Prototypes/Entities/Mobs/Species/harpy.yml
@@ -24,6 +24,8 @@
       - map: [ "underpants" ]
       - map: [ "undershirt" ]
       - map: [ "socks" ]
+      - map: [ "enum.HumanoidVisualLayers.Underwear" ] # Floof, add underwear
+      - map: [ "enum.HumanoidVisualLayers.Undershirt" ] # Floof, add underwear
       - map: [ "jumpsuit" ]
       - map: ["enum.HumanoidVisualLayers.LFoot"]
       - map: ["enum.HumanoidVisualLayers.RFoot"]
diff --git a/Resources/Prototypes/Entities/Mobs/Species/moth.yml b/Resources/Prototypes/Entities/Mobs/Species/moth.yml
index b9ce75978a8..d1f86f339a2 100644
--- a/Resources/Prototypes/Entities/Mobs/Species/moth.yml
+++ b/Resources/Prototypes/Entities/Mobs/Species/moth.yml
@@ -80,6 +80,8 @@
       - map: [ "enum.HumanoidVisualLayers.LArm" ]
       - map: [ "enum.HumanoidVisualLayers.RLeg" ]
       - map: [ "enum.HumanoidVisualLayers.LLeg" ]
+      - map: [ "enum.HumanoidVisualLayers.Underwear" ] # Floof, add underwear
+      - map: [ "enum.HumanoidVisualLayers.Undershirt" ] # Floof, add underwear
       - map: [ "jumpsuit" ]
       - map: [ "enum.HumanoidVisualLayers.LHand" ]
       - map: [ "enum.HumanoidVisualLayers.RHand" ]
diff --git a/Resources/Prototypes/Entities/Mobs/Species/shadowkin.yml b/Resources/Prototypes/Entities/Mobs/Species/shadowkin.yml
index 71dabd42ab6..ea8053ff8d3 100644
--- a/Resources/Prototypes/Entities/Mobs/Species/shadowkin.yml
+++ b/Resources/Prototypes/Entities/Mobs/Species/shadowkin.yml
@@ -160,6 +160,8 @@
         - map: ["enum.HumanoidVisualLayers.LFoot"]
         - map: ["enum.HumanoidVisualLayers.RFoot"]
         - map: ["socks"]
+        - map: [ "enum.HumanoidVisualLayers.Underwear" ] # Floof, add underwear
+        - map: [ "enum.HumanoidVisualLayers.Undershirt" ] # Floof, add underwear
         - map: ["underpants"]
         - map: ["undershirt"]
         - map: ["jumpsuit"]
diff --git a/Resources/Prototypes/Floof/Entities/Mobs/Customization/Markings/undershirt.yml b/Resources/Prototypes/Floof/Entities/Mobs/Customization/Markings/undershirt.yml
new file mode 100644
index 00000000000..38e2da8be3a
--- /dev/null
+++ b/Resources/Prototypes/Floof/Entities/Mobs/Customization/Markings/undershirt.yml
@@ -0,0 +1,111 @@
+- type: marking
+  id: UndershirtStandard
+  bodyPart: Undershirt
+  markingCategory: Undershirt
+  speciesRestriction: [Shadowkin, Diona, Arachnid, Reptilian, Moth, SlimePerson, Resomi, Rodentia, Human, Rodentia, Felinid, Oni, Vulpkanin, Harpy]
+  coloring:
+    default:
+      type:
+        !type:SimpleColoring
+          color: "#FFFFFF"
+  sprites:
+  - sprite: Floof/Mobs/Customization/undershirt.rsi
+    state: t_undershirt
+
+- type: marking
+  id: UndershirtSleeveless
+  bodyPart: Undershirt
+  markingCategory: Undershirt
+  speciesRestriction: [Shadowkin, Diona, Arachnid, Reptilian, Moth, SlimePerson, Resomi, Rodentia, Human, Rodentia, Felinid, Oni, Vulpkanin, Harpy]
+  coloring:
+    default:
+      type:
+        !type:SimpleColoring
+          color: "#FFFFFF"
+  sprites:
+  - sprite: Floof/Mobs/Customization/undershirt.rsi
+    state: t_undershirt_sleeveless
+
+- type: marking
+  id: UndershirtRolled
+  bodyPart: Undershirt
+  markingCategory: Undershirt
+  speciesRestriction: [Shadowkin, Diona, Arachnid, Reptilian, Moth, SlimePerson, Resomi, Rodentia, Human, Rodentia, Felinid, Oni, Vulpkanin, Harpy]
+  coloring:
+    default:
+      type:
+        !type:SimpleColoring
+          color: "#FFFFFF"
+  sprites:
+  - sprite: Floof/Mobs/Customization/undershirt.rsi
+    state: t_rolled_undershirt
+
+- type: marking
+  id: UndershirtRolledSleeveless
+  bodyPart: Undershirt
+  markingCategory: Undershirt
+  speciesRestriction: [Shadowkin, Diona, Arachnid, Reptilian, Moth, SlimePerson, Resomi, Rodentia, Human, Rodentia, Felinid, Oni, Vulpkanin, Harpy]
+  coloring:
+    default:
+      type:
+        !type:SimpleColoring
+          color: "#FFFFFF"
+  sprites:
+  - sprite: Floof/Mobs/Customization/undershirt.rsi
+    state: t_rolled_undershirt_sleeveless
+
+- type: marking
+  id: UndershirtLong
+  bodyPart: Undershirt
+  markingCategory: Undershirt
+  speciesRestriction: [Shadowkin, Diona, Arachnid, Reptilian, Moth, SlimePerson, Resomi, Rodentia, Human, Rodentia, Felinid, Oni, Vulpkanin, Harpy]
+  coloring:
+    default:
+      type:
+        !type:SimpleColoring
+          color: "#FFFFFF"
+  sprites:
+  - sprite: Floof/Mobs/Customization/undershirt.rsi
+    state: t_long_undershirt
+
+- type: marking
+  id: UndershirtClassic
+  bodyPart: Undershirt
+  markingCategory: Undershirt
+  speciesRestriction: [Shadowkin, Diona, Arachnid, Reptilian, Moth, SlimePerson, Resomi, Rodentia, Human, Rodentia, Felinid, Oni, Vulpkanin, Harpy]
+  coloring:
+    default:
+      type:
+        !type:SimpleColoring
+          color: "#FFFFFF"
+  sprites:
+  - sprite: Floof/Mobs/Customization/undershirt.rsi
+    state: snow_bra
+
+- type: marking
+  id: UndershirtSports
+  bodyPart: Undershirt
+  markingCategory: Undershirt
+  speciesRestriction: [Shadowkin, Diona, Arachnid, Reptilian, Moth, SlimePerson, Resomi, Rodentia, Human, Rodentia, Felinid, Oni, Vulpkanin, Harpy]
+  coloring:
+    default:
+      type:
+        !type:SimpleColoring
+          color: "#FFFFFF"
+  sprites:
+  - sprite: Floof/Mobs/Customization/undershirt.rsi
+    state: snow_sports
+
+- type: marking
+  id: UndershirtStrapless
+  bodyPart: Undershirt
+  markingCategory: Undershirt
+  speciesRestriction: [Shadowkin, Diona, Arachnid, Reptilian, Moth, SlimePerson, Resomi, Rodentia, Human, Rodentia, Felinid, Oni, Vulpkanin, Harpy]
+  coloring:
+    default:
+      type:
+        !type:SimpleColoring
+          color: "#FFFFFF"
+  sprites:
+  - sprite: Floof/Mobs/Customization/undershirt.rsi
+    state: snow_strapless
diff --git a/Resources/Prototypes/Floof/Entities/Mobs/Customization/Markings/underwear.yml b/Resources/Prototypes/Floof/Entities/Mobs/Customization/Markings/underwear.yml
new file mode 100644
index 00000000000..5b9b8cee2c2
--- /dev/null
+++ b/Resources/Prototypes/Floof/Entities/Mobs/Customization/Markings/underwear.yml
@@ -0,0 +1,69 @@
+- type: marking
+  id: UnderwearBoxers
+  bodyPart: Underwear
+  markingCategory: Underwear
+  speciesRestriction: [Shadowkin, Diona, Arachnid, Reptilian, Moth, SlimePerson, Resomi, Rodentia, Human, Rodentia, Felinid, Oni, Vulpkanin, Harpy]
+  coloring:
+    default:
+      type:
+        !type:SimpleColoring
+          color: "#FFFFFF"
+  sprites:
+  - sprite: Floof/Mobs/Customization/underwear.rsi
+    state: snow_boxers
+
+- type: marking
+  id: UnderwearLowriders
+  bodyPart: Underwear
+  markingCategory: Underwear
+  speciesRestriction: [Shadowkin, Diona, Arachnid, Reptilian, Moth, SlimePerson, Resomi, Rodentia, Human, Rodentia, Felinid, Oni, Vulpkanin, Harpy]
+  coloring:
+    default:
+      type:
+        !type:SimpleColoring
+          color: "#FFFFFF"
+  sprites:
+  - sprite: Floof/Mobs/Customization/underwear.rsi
+    state: snow_lowriders
+
+- type: marking
+  id: UnderwearBriefs
+  bodyPart: Underwear
+  markingCategory: Underwear
+  speciesRestriction: [Shadowkin, Diona, Arachnid, Reptilian, Moth, SlimePerson, Resomi, Rodentia, Human, Rodentia, Felinid, Oni, Vulpkanin, Harpy]
+  coloring:
+    default:
+      type:
+        !type:SimpleColoring
+          color: "#FFFFFF"
+  sprites:
+  - sprite: Floof/Mobs/Customization/underwear.rsi
+    state: snow_briefs
+
+- type: marking
+  id: UnderwearSatin
+  bodyPart: Underwear
+  markingCategory: Underwear
+  speciesRestriction: [Shadowkin, Diona, Arachnid, Reptilian, Moth, SlimePerson, Resomi, Rodentia, Human, Rodentia, Felinid, Oni, Vulpkanin, Harpy]
+  coloring:
+    default:
+      type:
+        !type:SimpleColoring
+          color: "#FFFFFF"
+  sprites:
+  - sprite: Floof/Mobs/Customization/underwear.rsi
+    state: snow_satin
+
+- type: marking
+  id: UnderwearTanga
+  bodyPart: Underwear
+  markingCategory: Underwear
+  speciesRestriction: [Shadowkin, Diona, Arachnid, Reptilian, Moth, SlimePerson, Resomi, Rodentia, Human, Rodentia, Felinid, Oni, Vulpkanin, Harpy]
+  coloring:
+    default:
+      type:
+        !type:SimpleColoring
+          color: "#FFFFFF"
+  sprites:
+  - sprite: Floof/Mobs/Customization/underwear.rsi
+    state: snow_tanga
diff --git a/Resources/Prototypes/Floof/Interactions/underwear_interactions.yml b/Resources/Prototypes/Floof/Interactions/underwear_interactions.yml
new file mode 100644
index 00000000000..c990aa5996e
--- /dev/null
+++ b/Resources/Prototypes/Floof/Interactions/underwear_interactions.yml
@@ -0,0 +1,39 @@
+- type: Interaction
+  parent: [BaseGlobal, BaseHands]
+  id: ToggleUndershirt
+  priority: -11
+  delay: 3
+  allowSelfInteract: true
+  hideByRequirement: true
+  requirement:
+    !type:ComplexRequirement
+    requirements:
+    - !type:EntityWhitelistRequirement
+      whitelist:
+        components: [HumanoidAppearance]
+    - !type:ClothingSlotBlacklistRequirement
+      slot: jumpsuit
+  effectSuccess:
+    popup: Obvious
+    sound: {path: /Audio/Effects/thudswoosh.ogg}
+    soundPerceivedByOthers: false
+  action:
+    !type:ToggleLayersAction
+    neededMarkingCategory: Undershirt
+    toggleLayers:
+    - Undershirt
+
+- type: Interaction
+  parent: ToggleUndershirt
+  id: ToggleUnderwear
+  priority: -12
+  delay: 2.2
+  effectSuccess:
+    popup: Obvious
+    sound: {path: /Audio/Effects/thudswoosh.ogg}
+    soundPerceivedByOthers: false
+  action:
+    !type:ToggleLayersAction
+    neededMarkingCategory: Underwear
+    toggleLayers:
+    - Underwear
diff --git a/Resources/Prototypes/Species/arachne.yml b/Resources/Prototypes/Species/arachne.yml
index 7daf122a197..04e9fa634eb 100644
--- a/Resources/Prototypes/Species/arachne.yml
+++ b/Resources/Prototypes/Species/arachne.yml
@@ -18,6 +18,9 @@
 - type: markingPoints
   id: MobArachneMarkingLimits
   points:
+    Undershirt:
+      points: 1
+      required: false # Floof, add underwear
     Hair:
       points: 1
       required: false
@@ -59,6 +62,8 @@
     Head: MobHumanHead
     Hair: MobHumanoidAnyMarking
     Chest: MobHumanTorso
+    Underwear: MobHumanoidAnyMarking
+    Undershirt: MobHumanoidAnyMarking
     Eyes: MobArachneEyes
     LArm: MobHumanLArm
     RArm: MobHumanRArm
diff --git a/Resources/Prototypes/Species/arachnid.yml b/Resources/Prototypes/Species/arachnid.yml
index a7965370639..66e9b3aacc0 100644
--- a/Resources/Prototypes/Species/arachnid.yml
+++ b/Resources/Prototypes/Species/arachnid.yml
@@ -21,6 +21,8 @@
     Head: MobArachnidHead
     Snout: MobHumanoidAnyMarking
     Chest: MobArachnidTorso
+    Underwear: MobHumanoidAnyMarking # Floof, add underwear
+    Undershirt: MobHumanoidAnyMarking # Floof, add underwear
     HeadTop: MobHumanoidAnyMarking
     HeadSide: MobHumanoidAnyMarking
     Tail: MobHumanoidAnyMarking
@@ -45,6 +47,13 @@
   id: MobArachnidMarkingLimits
   onlyWhitelisted: true
   points:
+    Underwear:
+      points: 1
+      required: true
+      defaultMarkings: [ UnderwearBoxers ] # Floof, add underwear
+    Undershirt:
+      points: 1
+      required: false # Floof, add underwear
     Hair:
       points: 0
       required: false
diff --git a/Resources/Prototypes/Species/diona.yml b/Resources/Prototypes/Species/diona.yml
index 2edd329103e..689b57018f5 100644
--- a/Resources/Prototypes/Species/diona.yml
+++ b/Resources/Prototypes/Species/diona.yml
@@ -21,6 +21,8 @@
     HeadTop: MobHumanoidAnyMarking
     HeadSide: MobHumanoidAnyMarking
     Chest: MobDionaTorso
+    Underwear: MobHumanoidAnyMarking # Floof, add underwear
+    Undershirt: MobHumanoidAnyMarking # Floof, add underwear
     Eyes: MobDionaEyes
     LArm: MobDionaLArm
     RArm: MobDionaRArm
@@ -37,6 +39,13 @@
   id: MobDionaMarkingLimits
   onlyWhitelisted: true
   points:
+    Underwear:
+      points: 1
+      required: true
+      defaultMarkings: [ UnderwearBoxers ] # Floof, add underwear
+    Undershirt:
+      points: 1
+      required: false # Floof, add underwear
     Head:
       points: 2
       required: false
diff --git a/Resources/Prototypes/Species/harpy.yml b/Resources/Prototypes/Species/harpy.yml
index bb6e04fe372..55676f30d3f 100644
--- a/Resources/Prototypes/Species/harpy.yml
+++ b/Resources/Prototypes/Species/harpy.yml
@@ -23,6 +23,8 @@
     FacialHair: MobHumanoidAnyMarking
     Snout: MobHumanoidAnyMarking
     Chest: MobHarpyTorso
+    Underwear: MobHumanoidAnyMarking # Floof, add underwear
+    Undershirt: MobHumanoidAnyMarking # Floof, add underwear
     HeadTop: MobHumanoidAnyMarking
     HeadSide: MobHumanoidAnyMarking
     Tail: MobHumanoidAnyMarking
@@ -41,6 +43,13 @@
 - type: markingPoints
   id: MobHarpyMarkingLimits
   points:
+    Underwear:
+      points: 1
+      required: true
+      defaultMarkings: [ UnderwearBoxers ] # Floof, add underwear
+    Undershirt:
+      points: 1 # Floof, add underwear
+      required: false
     Hair:
       points: 1
       required: false
diff --git a/Resources/Prototypes/Species/human.yml b/Resources/Prototypes/Species/human.yml
index 012fc4ba42d..88433dedf6d 100644
--- a/Resources/Prototypes/Species/human.yml
+++ b/Resources/Prototypes/Species/human.yml
@@ -23,6 +23,8 @@
     FacialHair: MobHumanoidAnyMarking
     Snout: MobHumanoidAnyMarking
     Chest: MobHumanTorso
+    Underwear: MobHumanoidAnyMarking # Floof, add underwear
+    Undershirt: MobHumanoidAnyMarking # Floof, add underwear
     Eyes: MobHumanoidEyes
     LArm: MobHumanLArm
     RArm: MobHumanRArm
@@ -40,6 +42,13 @@
 - type: markingPoints
   id: MobHumanMarkingLimits
   points:
+    Underwear:
+      points: 1
+      required: true
+      defaultMarkings: [ UnderwearBoxers ] # Floof, add underwear
+    Undershirt:
+      points: 1
+      required: false # Floof, add underwear
     Hair:
       points: 1
       required: false
diff --git a/Resources/Prototypes/Species/ipc.yml b/Resources/Prototypes/Species/ipc.yml
index afebc7be190..10003dd2ad2 100644
--- a/Resources/Prototypes/Species/ipc.yml
+++ b/Resources/Prototypes/Species/ipc.yml
@@ -35,6 +35,8 @@
     Wings: MobHumanoidAnyMarking
     Hair: MobHumanoidMarkingMatchSkin
     Chest: MobIPCTorso
+    Underwear: MobHumanoidAnyMarking # Floof, add underwear
+    Undershirt: MobHumanoidAnyMarking # Floof, add underwear
     LArm: MobIPCLArm
     RArm: MobIPCRArm
     LHand: MobIPCLHand
diff --git a/Resources/Prototypes/Species/moth.yml b/Resources/Prototypes/Species/moth.yml
index 23dc9a98772..7254d605ced 100644
--- a/Resources/Prototypes/Species/moth.yml
+++ b/Resources/Prototypes/Species/moth.yml
@@ -19,6 +19,8 @@
     Head: MobMothHead
     Snout: MobHumanoidAnyMarking
     Chest: MobMothTorso
+    Underwear: MobHumanoidAnyMarking # Floof, add underwear
+    Undershirt: MobHumanoidAnyMarking # Floof, add underwear
     HeadTop: MobHumanoidAnyMarking
     HeadSide: MobHumanoidAnyMarking
     Tail: MobHumanoidAnyMarking
@@ -42,6 +44,13 @@
   id: MobMothMarkingLimits
   onlyWhitelisted: true
   points:
+    Underwear:
+      points: 1
+      required: true
+      defaultMarkings: [ UnderwearBoxers ] # Floof, add underwear
+    Undershirt:
+      points: 1 # Floof, add underwear
+      required: false
     Hair:
       points: 0
       required: false
diff --git a/Resources/Prototypes/Species/reptilian.yml b/Resources/Prototypes/Species/reptilian.yml
index 0cfd6d89456..29d3270c463 100644
--- a/Resources/Prototypes/Species/reptilian.yml
+++ b/Resources/Prototypes/Species/reptilian.yml
@@ -25,6 +25,8 @@
     Head: MobReptilianHead
     Snout: MobHumanoidAnyMarking
     Chest: MobReptilianTorso
+    Underwear: MobHumanoidAnyMarking # Floof, add underwear
+    Undershirt: MobHumanoidAnyMarking # Floof, add underwear
     HeadTop: MobHumanoidAnyMarking
     HeadSide: MobHumanoidAnyMarking
     Tail: MobHumanoidAnyMarking
@@ -43,6 +45,13 @@
   id: MobReptilianMarkingLimits
   onlyWhitelisted: true
   points:
+    Underwear:
+      points: 1
+      required: true
+      defaultMarkings: [ UnderwearBoxers ] # Floof, add underwear
+    Undershirt:
+      points: 1 # Floof, add underwear
+      required: false
     Hair:
       points: 0
       required: false
diff --git a/Resources/Prototypes/Species/shadowkin.yml b/Resources/Prototypes/Species/shadowkin.yml
index 7cbd752092f..dc6d23ef0b2 100644
--- a/Resources/Prototypes/Species/shadowkin.yml
+++ b/Resources/Prototypes/Species/shadowkin.yml
@@ -35,6 +35,8 @@
     HeadSide: MobShadowkinAnyMarkingFollowSkin
     Tail: MobShadowkinAnyMarkingFollowSkin
     Chest: MobShadowkinTorso
+    Underwear: MobHumanoidAnyMarking # Floof, add underwear
+    Undershirt: MobHumanoidAnyMarking # Floof, add underwear
     Eyes: MobShadowkinEyes
     LArm: MobShadowkinLArm
     RArm: MobShadowkinRArm
@@ -48,6 +50,13 @@
 - type: markingPoints
   id: MobShadowkinMarkingLimits
   points:
+    Underwear:
+      points: 1
+      required: true
+      defaultMarkings: [ UnderwearBoxers ] # Floof, add underwear
+    Undershirt:
+      points: 1
+      required: false # Floof, add underwear
     Tail:
       points: 1
       required: true
diff --git a/Resources/Prototypes/Species/skeleton.yml b/Resources/Prototypes/Species/skeleton.yml
index 1f2a95e9918..4c4066e18f1 100644
--- a/Resources/Prototypes/Species/skeleton.yml
+++ b/Resources/Prototypes/Species/skeleton.yml
@@ -16,6 +16,8 @@
   sprites:
     Head: MobSkeletonHead
     Chest: MobSkeletonTorso
+    Underwear: MobHumanoidAnyMarking # Floof, add underwear
+    Undershirt: MobHumanoidAnyMarking # Floof, add underwear
     LArm: MobSkeletonLArm
     RArm: MobSkeletonRArm
     LHand: MobSkeletonLHand
diff --git a/Resources/Prototypes/Species/slime.yml b/Resources/Prototypes/Species/slime.yml
index f7b8adf2eff..60c36c6fdc0 100644
--- a/Resources/Prototypes/Species/slime.yml
+++ b/Resources/Prototypes/Species/slime.yml
@@ -18,6 +18,8 @@
     FacialHair: MobSlimeMarkingFollowSkin
     Snout: MobSlimeMarkingFollowSkin
     Chest: MobSlimeTorso
+    Underwear: MobHumanoidAnyMarking # Floof, add underwear
+    Undershirt: MobHumanoidAnyMarking # Floof, add underwear
     HeadTop: MobSlimeMarkingFollowSkin
     HeadSide: MobSlimeMarkingFollowSkin
     Tail: MobSlimeMarkingFollowSkin
@@ -35,6 +37,13 @@
 - type: markingPoints
   id: MobSlimeMarkingLimits
   points:
+    Underwear:
+      points: 1
+      required: true
+      defaultMarkings: [ UnderwearBoxers ] # Floof, add underwear
+    Undershirt:
+      points: 1
+      required: false # Floof, add underwear
     Hair:
       points: 1
       required: false
diff --git a/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/meta.json b/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/meta.json
new file mode 100644
index 00000000000..a26b06084a8
--- /dev/null
+++ b/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/meta.json
@@ -0,0 +1,43 @@
+{
+  "version": 1,
+  "license": "CC-BY-SA-3.0",
+  "copyright": "Taken and modified from cmss13 at https://github.com/cmss13-devs/cmss13/blob/884ab172389b6fc54ef063f5fbea5e8b0a0a2235/icons/mob/humans/undershirt.dmi",
+  "size": {
+    "x": 32,
+    "y": 32
+  },
+  "states": [
+    {
+      "name": "t_undershirt",
+      "directions": 4
+    },
+    {
+      "name": "t_undershirt_sleeveless",
+      "directions": 4
+    },
+    {
+      "name": "t_rolled_undershirt",
+      "directions": 4
+    },
+    {
+      "name": "t_rolled_undershirt_sleeveless",
+      "directions": 4
+    },
+    {
+      "name": "t_long_undershirt",
+      "directions": 4
+    },
+    {
+      "name": "snow_bra",
+      "directions": 4
+    },
+    {
+      "name": "snow_sports",
+      "directions": 4
+    },
+    {
+      "name": "snow_strapless",
+      "directions": 4
+    }
+  ]
+}
diff --git a/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/snow_bra.png b/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/snow_bra.png
new file mode 100644
index 00000000000..5e1231602f6
Binary files /dev/null and b/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/snow_bra.png differ
diff --git a/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/snow_sports.png b/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/snow_sports.png
new file mode 100644
index 00000000000..65bbeaefce9
Binary files /dev/null and b/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/snow_sports.png differ
diff --git a/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/snow_strapless.png b/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/snow_strapless.png
new file mode 100644
index 00000000000..b27b44860e3
Binary files /dev/null and b/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/snow_strapless.png differ
diff --git a/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/t_long_undershirt.png b/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/t_long_undershirt.png
new file mode 100644
index 00000000000..3e16fc0a532
Binary files /dev/null and b/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/t_long_undershirt.png differ
diff --git a/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/t_rolled_undershirt.png b/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/t_rolled_undershirt.png
new file mode 100644
index 00000000000..786eb63f4d7
Binary files /dev/null and b/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/t_rolled_undershirt.png differ
diff --git a/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/t_rolled_undershirt_sleeveless.png b/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/t_rolled_undershirt_sleeveless.png
new file mode 100644
index 00000000000..59d93e8ef73
Binary files /dev/null and b/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/t_rolled_undershirt_sleeveless.png differ
diff --git a/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/t_undershirt.png b/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/t_undershirt.png
new file mode 100644
index 00000000000..9e953adc767
Binary files /dev/null and b/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/t_undershirt.png differ
diff --git a/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/t_undershirt_sleeveless.png b/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/t_undershirt_sleeveless.png
new file mode 100644
index 00000000000..96432de20d7
Binary files /dev/null and b/Resources/Textures/Floof/Mobs/Customization/undershirt.rsi/t_undershirt_sleeveless.png differ
diff --git a/Resources/Textures/Floof/Mobs/Customization/underwear.rsi/meta.json b/Resources/Textures/Floof/Mobs/Customization/underwear.rsi/meta.json
new file mode 100644
index 00000000000..78d8f7eab41
--- /dev/null
+++ b/Resources/Textures/Floof/Mobs/Customization/underwear.rsi/meta.json
@@ -0,0 +1,31 @@
+{
+  "version": 1,
+  "license": "CC-BY-SA-3.0",
+  "copyright": "Take from https://github.com/cmss13-devs/cmss13/blob/884ab172389b6fc54ef063f5fbea5e8b0a0a2235/icons/mob/humans/underwear.dmi",
+  "size": {
+    "x": 32,
+    "y": 32
+  },
+  "states": [
+    {
+      "name": "snow_boxers",
+      "directions": 4
+    },
+    {
+      "name": "snow_lowriders",
+      "directions": 4
+    },
+    {
+      "name": "snow_briefs",
+      "directions": 4
+    },
+    {
+      "name": "snow_satin",
+      "directions": 4
+    },
+    {
+      "name": "snow_tanga",
+      "directions": 4
+    }
+  ]
+}
diff --git a/Resources/Textures/Floof/Mobs/Customization/underwear.rsi/snow_boxers.png b/Resources/Textures/Floof/Mobs/Customization/underwear.rsi/snow_boxers.png
new file mode 100644
index 00000000000..e49b8b72773
Binary files /dev/null and b/Resources/Textures/Floof/Mobs/Customization/underwear.rsi/snow_boxers.png differ
diff --git a/Resources/Textures/Floof/Mobs/Customization/underwear.rsi/snow_briefs.png b/Resources/Textures/Floof/Mobs/Customization/underwear.rsi/snow_briefs.png
new file mode 100644
index 00000000000..2eab274ab7e
Binary files /dev/null and b/Resources/Textures/Floof/Mobs/Customization/underwear.rsi/snow_briefs.png differ
diff --git a/Resources/Textures/Floof/Mobs/Customization/underwear.rsi/snow_lowriders.png b/Resources/Textures/Floof/Mobs/Customization/underwear.rsi/snow_lowriders.png
new file mode 100644
index 00000000000..7bf2266a04f
Binary files /dev/null and b/Resources/Textures/Floof/Mobs/Customization/underwear.rsi/snow_lowriders.png differ
diff --git a/Resources/Textures/Floof/Mobs/Customization/underwear.rsi/snow_satin.png b/Resources/Textures/Floof/Mobs/Customization/underwear.rsi/snow_satin.png
new file mode 100644
index 00000000000..e7939ebc756
Binary files /dev/null and b/Resources/Textures/Floof/Mobs/Customization/underwear.rsi/snow_satin.png differ
diff --git a/Resources/Textures/Floof/Mobs/Customization/underwear.rsi/snow_tanga.png b/Resources/Textures/Floof/Mobs/Customization/underwear.rsi/snow_tanga.png
new file mode 100644
index 00000000000..0b6d238079b
Binary files /dev/null and b/Resources/Textures/Floof/Mobs/Customization/underwear.rsi/snow_tanga.png differ