shack-cident
The act of accidental shacking. Shacking with someone you didn't intend to or would never want under normal circumstances. Can also refer a person that you would shack with by accident.
"So I here you hooked up with that ugly skank from the bar last night?"
"Yea, it was a shack-cident."
or
"I guess I'd hook up with him, but he's a total shack-cident."
"Yea, it was a shack-cident."
or
"I guess I'd hook up with him, but he's a total shack-cident."