A MIRF is the exact opposite of a milf. While a milf is a mother that someone would like fuck( bang the shit out of) a mirf is a mother that someone would regret fucking( really bad pussy haha.)
juliets mom is fucking hot and is definetly a milf. but john's mom is a mirf. I totally regret fucking her, her pussy smelled like rotten fish and dam did she need to shave or what.