the act of creeping into a blacked out person's bed with the intent of hooking up
Aron: Did you hear about Jill?
Melissa: No! What...?
Aron: She got crunked and passed out at Eric's party last Saturday and woke up to him giving her a sleepy jenkins!
Melissa: Ew!! What a creep! I hope he doesn't try that shit at my parties...