SE Extension

Overview

The SE Extension (SA_A2XL_R18.prefab) is an R18 expansion part added non-destructively via Modular Avatar. Adding it to the base avatar enables the following features.

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Menu Structure

Automatically integrated into the top menu by MA Menu Installer.

R18 Menu
├─ PubicHair (ON/OFF)
├─ Clitoris (Radial)
├─ Nipple_L (Radial)
├─ Nipple_R (Radial)
└─ Pussy_Open (Radial)

	PubicHair	Toggles pubic hair visibility. The setting is saved (saved: true).
	Clitoris	Displays clitoral contact intensity in real time. Synced during the session only (saved: false).
	Nipple_L	Displays left nipple contact intensity in real time. Synced during the session only (saved: false).
	Nipple_R	Displays right nipple contact intensity in real time. Synced during the session only (saved: false).
	Pussy_Open	Manually adjusts the open/close state. Synced during the session only (saved: false).

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Contact Detection System (ContactReceiver)

VRChat's ContactReceiver component detects contact from other players and the avatar itself.

Sensor	Detection Area	Accepted Tags	Detection Radius
Sen_Clit	Clitoris	Foot / Finger	0.02m
L_Sen_Nipple	Left nipple	Foot / Finger	0.025m
R_Sen_Nipple	Right nipple	Foot / Finger	0.025m

Common settings for all sensors:

• allowSelf: true — detects contact from the avatar itself
• allowOthers: true — detects contact from other players
• minVelocity: 0.05 — minimum velocity filter (prevents false positives)

Parameter Structure

The contact detection system operates by combining two types of parameters: Bool and Float.

Parameter	Type	Role
Clitoris_Contact	Bool	Whether contact is currently occurring (written directly by ContactReceiver)
Nipple_L_Contact	Bool	Left nipple contact flag
Nipple_R_Contact	Bool	Right nipple contact flag
Clitoris	Float	Accumulated clitoral contact intensity (0.0–1.0)
Nipple_L	Float	Accumulated left nipple contact intensity (0.0–1.0)
Nipple_R	Float	Accumulated right nipple contact intensity (0.0–1.0)

The _Contact Bool parameters represent real-time "currently touching" state, while the Float parameters accumulate as a running total of contact history. Float parameters are synced: true / saved: false — synced during the session only, and reset on logout.

Value Increase/Decrease Logic

While contact is active (_Contact = true), the corresponding Float value increases at +0.02/tick. When contact ends, the SYS_NSFW_Contact_Subtract layer activates and gradually decreases the value at -0.02/tick as long as it is 0.2 or above. This creates a natural lingering sensation after contact ends.

When the Float value exceeds 0.99, a transition to a special state occurs:

Area	Threshold	Destination State
Clitoris	Clitoris > 0.99	CLITORIS_ORGASM
Left nipple	Nipple_L > 0.99	LACTATION_L
Right nipple	Nipple_R > 0.99	LACTATION_R

Animator Layer Structure

The R18FX Controller is structured with independent layers for each function.

Layer	Role
SYS_NSFW_Contact_Subtract	System that automatically decreases Float values when contact ends
FX_CLITORIS_CONTACT	Increments Clitoris during contact and transitions to orgasm at the upper limit
FX_NIPPLE_L_CONTACT	Increments Nipple_L during contact and transitions to lactation at the upper limit
FX_NIPPLE_R_CONTACT	Increments Nipple_R during contact and transitions to lactation at the upper limit
FX_CLITORIS_ERECTION	Drives the LocalScale of the Clit bone based on the Clitoris value
FX_NIPPLE_L_ERECTION	Drives the LocalPosition of the Nipple.L bone based on the Nipple_L value
FX_NIPPLE_R_ERECTION	Drives the LocalPosition of the Nipple.R bone based on the Nipple_R value
FX_PUSSY_OPEN	Controls SPS act_(i)_open and the urination emitter via Pussy_Open

Note When Modifying

The IDLE state of the FX_PUSSY_OPEN layer has a transition condition of CostumeBody = 2 (undressed state). If the default costume is removed, this condition will not be met and PUSSY_OPEN will not function.

Solutions:

• Delete the CostumeBody parameter from SA_A2XL_SE R18FX and also remove the condition from the IDLE state of the FX_PUSSY_OPEN layer.
• Alternatively, assign CostumeBody = 2 to the undressed state of your custom costume.

Animation Drive Method

ERECTION layers use m_TimeParameterActive: true to directly control the animation playback position (Time) with the Float parameter value. This means "value 0.0 = default shape / value 1.0 = maximum deformation" is reflected in real time in proportion to the Float value.

Animation	Control Target	Method
CLITORIS_ERECTION	Armature/Hips/Clit	Changes bone LocalScale
NIPPLE_L_ERECTION	Armature/.../Nipple.L	Changes bone LocalPosition
NIPPLE_R_ERECTION	Armature/.../Nipple.R	Changes bone LocalPosition
PUSSY_OPEN	Basebody / Peeing_System	SPS act_(i)_open + IsActive of urination emitter

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SPS (VRCFury Sexual Penetration System)

A penetration depth detection system using VRCFury v1.1174.0. Operates independently of ContactReceiver.

Object	SPS Name	Corresponding BlendShape
Pussy	おまんこ	act_(i)_push / open_half1 / open_half2
Anus	あなる	act_*_push / open_half1 / open_half2

BlendShapes are driven automatically in proportion to penetration depth. Automatic detection is enabled via enableAuto: true.

Non-destructive integration into the base avatar's bone hierarchy is achieved via ArmatureLink (linkMode: 4).

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PhysBone (Physics)

Area	immobile	limitType	maxAngleX	maxAngleZ
Clitoris	1.0	Angle	10°	45°
Labia ×2	1.0	Angle	10°	45°

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Parameter List

Parameter	Type	saved	synced	Description
PubicHair	Bool	✓	✓	Pubic hair visibility
Clitoris	Float	✗	✓	Clitoral contact intensity
Nipple_L	Float	✗	✓	Left nipple contact intensity
Nipple_R	Float	✗	✓	Right nipple contact intensity
Pussy_Open	Float	✗	✓	Open/close state