Replace their shampoo with Super glue Or you could duct tape them to their bed while they're asleep an leave them there.
Make sure it's permanent marker perhaps you could steal all their clothes as well except for something embarrassing?
I only pull pranks on my boyfriend. Do I want to walk around with his lumpy head out there for the world to see? No.
Ohhh, put a dog collar shocker thing on them and when they walk out of their room or something it'll shock them. Or Handcuff them to the bedpost
Shave your name into the top of their head! That would be cool... Or shave someone else name into their head/hair.
My roommate is evil. How evil? Satanist evil. He put pentagrams around the house. Just carved them there. I can show proof. ._.
One of the pentagrams. Hope you can see it. Couldn't take a picture of the other one. Not enough light.
I like girlonfire's I'm gonna try that one And shaving someone's head is a little too much... That's something to fight over... Just shave off one of their eyebrows
Stab'em in the back while they are eating. One thing: STAB STAB STAB STAB STAB STAB STAB and then STAB STAB STAB STAB STAB STAB STAB STAB!!!!!!! jk