Suicide, I reckon.

Yeah, then give them to all your student… We'll get you outside, we'll air you out… Let's finish this off tonight. I know he's not conscious. Oh, my God. Have you called them? Before, wait, can you turn that off? Greetings esteemed carbon based lifeform Hi, is he in here? What's wrong with his eyes? Only you thought you could get rid of it… Recently passed away? No, it's fine. I go in there maybe five times a day. You've got just as much guilt and remors…