Venom thrashing vest

this vest just came to be because i had a lot of patches i wasn't really using and i put em on this rag that i bought at goodwill for under $10. the problem here is, this is a really cheap womens jacket that i cut the sleaves off of, and it's shaped a little weird in the back: it sort of flairs in the back, like bellbottoms. it sucks. most people say they don't notice, but it's kinda weird. i dunno, for some reason i've become very self consious lately, maybe it's time to get that lobotomy i've always wanted.

anyone know how to fix that? my room mate says he can fix it, but i dunno. he says it doesn't need fixing.