if a girl blows off her friends, or just hangs out with her boy instead of her girlies, and they're offended cuz they know they love her more.
similiar to guys's bro's before hoe's
Ali: aww, come on kate! sisters before mister's!!
Ali: hey kate come over to our table!! we got wings...
Kate;: hahaha no sorry, Ben already ordered wings too..
Ali: ugh, sisters before mister's!
Better known as ladies first and to hell with your boyfriend.
Sometimes called chicks before dicks.