Wolf spider female genital region, commonly known as spider pussy. This two pocket structure receives sperm from the male. In some species the male part snaps off after ejaculation and plugs the female on one side. Luckily she still has another entrance for another male to use. A lovely evolutionary biology theory "Cryptic female Choice" is that the sperm continue their Darwinian battle inside of her, thereby shifting control of sperm selection to the female. As an artist, this feminist twist of Survival of the Fittest arouses my interest deeply.