Obsessive Compulsive SLAG Disorder
They have a mental issue where they can't help being the worst slag ever. They do slaggy things all the time, like they're on fire.
She texts a guy she met at the chip shop 3 times a day, even though he blocked her.
She gives head to a guy in the graveyard even though he's dead.
She sends a tweet to a random guy at 2 am with a photo of her face.