A group of girls who are so self absorbed in how they dress, and what their makeup looks like that they come across as major airheads who only flutter around in packs or herds.
Oh great, here come the Twinkie Brigade. I hope they aren't in my class cause they can be so airheaded at times. Plus, I don't want to share my makeup or let them borrow my clothes. They are so me, me, me.