A rare kind of human with an ass for a face.

Often seen on the 21th plantet in the solasystem: Planet BF (Planet Buttface)

Offensive words which Buttfaces don't like:
Assface, Dickface, Cracker, Crackface, Faceass and Ass Overlord.

Current Leader of Plantet buttface : Captain Buttface

Buttfaces Pray to Lord Buttface and Captain Buttface every single day and night to keep there lives.

Briefly, "the realization that each random passerby is living a life as vivid and complex as your own." Originally from the Dictionary of Obscure Sorrows, which has a lot more beautiful neologism definitions like this you might enjoy.

A person with an unappealing face.

N. a person who you secretly love and just can't stop thinking about, even though you know you should. (by calling someone a buttface you cover up the fact in a flirty way that you love them)

This isn't really a harsh name to call someone at all. More times than not it is used by close friends especially male/female friends or even siblings. There is a major difference in calling a person an "Ass head" as compared to "Butt Face"

a horrible ailment of which the sufferer has an ass for a face.
instead of talking, they emit large amounts of methane gas from slitted pores located beneath their inverted nostrils. This is a painful process for both them, and the surrounding people.

An affectionate term for a friend, can also be shortened to Butt, Butty or Bum, especially when several Buttface's are in the room.

Buttface's can usually be found saying plom