A female who is a serial cheater. If her name is Emma, that girl has been more ran through than the finish line at a race. She flirts with every guy she speaks to shamelessly and sends most of them free nudies. If you're a man, don't date her because she WILL cheat on you. And if you're a woman don't let her near your boyfriend because she will try to fuck him behind your back while smiling in your face.
Example 1:
Person 1: Emma cheated on me again!
Person 2: Damn bro, third time this week?
Example 2:
Person 1: My homies and I ran a train on Emma last week, but when it was my turn to smash it felt like throwing a pencil down a corridor.
Person 2: You should get tested. Me and 2 other guys had her prior and got crabs. I got so many crabs in fact that I had to ask her if she planned on putting some sand in her vag next time to make them feel more at home.