It resumes to an texture overlay on body, in which the slider control it's opacity.
Since it's just a texture overlay I tried to find the texture files in which they are based to.
And here are the textures of them, found in DeltaBuild2.
(Hover the images for description)
Type & Group & Instance: 0x00B2D882 0x00000000 0xA28B589500895C8F
![Normal map which controls the Muscle tone for Males.](http://img401.imageshack.us/img401/5180/ambodycutness.png)
afBodyCutness (DDS File)
Type & Group & Instance: 0x00B2D882 0x00000000 0x86DB95357084C4E2
![Normal map which controls the Muscle tone for Females.](http://img25.imageshack.us/img25/2140/afbodycutness.png)
afBodyCleavage (DDS File)
Type & Group & Instance: 0x00B2D882 0x00000000 0x6731C72E72BABDF3
![Normal map which controls the Breast texture.](http://img194.imageshack.us/img194/8048/afbodycleavage.png)