Similar to kiss my ass, only deeper. Typically used in an escalating argument when a death blow is needed. Generally modified or enforced with fuck face, see example below.
Two people arguing:

person 1: Why are you such an douche-bag?

person 2: Go fuck yourself!

person 1: Fuck you!

person 2: Kiss my asshole, fuck face!
by zippojoker August 26, 2009
Get the kiss my asshole mug.