 And so for those people like me that doesn't have a flat butt, somebody hits my butt, it gives, and they get that bounce. Not something I want people to know about me, but that's just the way it is. The purpose of the butt, however, is supposed to protect our spine. But it also, the purpose of the butt is, with certain sexual positions, protects the male from being hurt and the female from being hurt. It provides there being a cushion.