Heather Lee: I'm really not okay with any of this. I mean, buying a Christmas present for a serial killer?
Melissa Kitt: No. You see, serial killers murder repeatedly for sexual thrill. Billy Lenz was a spree killer - dude just fucking lost it.
Ms. Barbara MacHenry: Didn't I see Clair earlier?
Kelli Presely: Isn't she upstairs writing a card to her sister?
Melissa Kitt: No, I think her sister picked her up earlier. Remember, this is the occasion for Clair and her sister and her mom to bury the hatchet and rediscover each other.
Dana Mathis: I'd like to bury the hatchet with my sister... right in her head.
Dana Mathis: Are you high? It's freezing out there.
Melissa Kitt: I'm sorry, but that-that fuckin' voice, that was not Megan or Kyle. That was the fucking devil, and he was not talking to us, he was talking to Billy.
Answer: Billy's mom is insane and does not possess a fully rational mind.