Buttywudder

The landing strip of bony flesh between a one's testicles or vulva and one's anus. Officially known as a perineum, and affectionately known as a gooch.

Rodney Galereux had gone at Nebu for a full blown ballsack wackalack hoping for the prize of some cherished banana points, but with seconds to spare, Nebu dodged the slap and Rodney's back-hand hit him square in the buttywudder.