look up any word, like pussy:
verb. To jump on someone while they are having sex, inadvertently joining the party.

Could be a hybrid slang of the German words "Bungschaft" (to borrow) and Schud (to thrust).
Kevin borosched at the party last night. He jumped in Chester's room to scare him only to discover that he was doing a chick.
by WhatHaveYou February 01, 2010