Perfuckit
It's when something looks look right on paper, sounds right in theory, or just seems logical at the moment until you really think about and you realize fuck that. To start something and end abruptly. Abort
I started to work on this science project and perfuckit... that's not going to work or you're hanging w/your boys and you're telling a story and after you start telling them you say perfuckit.... because you realized it was a lame ass story