Stiles does this thing where he plays with his mouth a lot. In class, out of class, he's always chewing on pencils or his hoodie or touching his lips with his fingers.

And Erica? It drives her nuts. She likes his mouth, likes the way it runs on and on, how easily it slides into a grin, especially when he's taking on Derek in a fight of wits and sarcasm.

She's wondered what it felt like. Was it soft? Maybe a little bit chapped, but yeah, probably soft. She found herself staring at it, this time during a study session, and she had her chin leaning on her hand, watching him talk but not really listening. She hated chemistry and not even Stiles could get her interested in what that dbag Harris had to teach. He's in the middle of a particularly vehement rant about alkalines when she decides, fuck it.

Grabbing him by the collar of his shirt, Erica pulls him forehead and plants one on him, darting her tongue out to lick at his bottom lip as she pulls away.