My roomate jerks off in the room

It's been happening the last few days. I would be woken by this body rubbing on bed noise. I open my eyes to see my roomate lying on his stomach, rubbing his crotch on the bed. Maybe he thinks he is being sneaky or whatever by doing that and not actually pumping but anyway. I close my eyes, try to close my ears, and pretend what is happening is not actually happening. I cannot look my roomate in the eyes anymore. I do not talk to him at all now. Fuck.

Tape it and post it on Youtube. That's always fun.
Or try putting Icy-hot on his bed. That always leads to good times.
"Stab him" is also an option.