Moss (v) To totally ruin someone or something irreperably.
"On no my life is mossed up.
I'm going to kill myself"
"Your such a loser, you totally mossed that one"
"That song is a bit moss"
"Is the drummer in time. No he's mossed it up again!"
"All you do is moss things up for me"
"Who's mossed your face up?"