What is Ass Jack-o-lantern?
the term ass jack-o-lantern is a somewhat more clever and (perhaps?) less childish way to call someone a butthead. it also implies that the person has a nasty face and is an enormous creeper (both of which are qualities possessed by a halloween jack-o-lantern)
the ass jack-o-lantern dated the girl that was way too good for him and wore a stupid hawaiian shirt.