it will be (one's) ass
rude slang One will incur severe negative consequences (as a result of something). I'm your boss, so it will be my ass if this report you've prepared for the CEO has any errors. You know it'll be your ass if Mom and Dad catch you sneaking out again.
It will be your ass!
Sl. You will pay dearly!; You will suffer the consequences. (Potentially offensive. Use only with discretion.) If you do that again, it will be your ass! It will be your ass if it isn't done right this time.
It will be your ass!
sent. It will cost you your ass!; You will pay dearly! (Usually objectionable.) It will be your ass if it isn’t done right this time.