backpfeifengesicht: literally means "a face that needs a fist in it." (pronounced back-pf-eye-fen-ge-zeesht)
there you go. your new insult. use it wisely.
some other suggested insults:
1) you're like f. scott fizgerald's screenplays. unknown and unnecessary.
2) your voice sounds like yoda with pneumonia.
3) you are a pumpkin on november 1
4) you tacky bulletin board.
5) you off-brand cheerio
6) you're about as famous as bobby frost
7) are you feeling okay? because i'm not. not after seeing your face.
8) you're that chair that even the cat won't sit on.
9) you broken cassette tape in an attic covered in sawdust and cat piss
10) are you corn? because you need to shut your mouth and consider your ears.
don't have a face that needs a fist in it. until next time.
