When the sticky white love-juice of a male is splurted onto the female's stomach, chest, arse, lower back ( or anywhere else that floats your boat. REFERENCE: In her hair ), and the manly love-mayonaise is gently massaged into the girl's skin, the skin becomes Moon Skin.
So-called because the skin shines in the moon when the process has been completed.. if you were to sit in the moonlight, that is.
Also known as FUPA (Fat Upper Pussy Area). This occurs after some very unattractive women have children. After they give birth, they have excess skin above their vagina. Hence the term, child skin.
"She gave good head, but her childskin was sagging to the grownd."