When he returned to prison Chopper was on library duty and as he walked into the other man's cell he pushed him to the floor and jumped on his head from the bed until he died.
The term Jam Jarring is now employed as a means of conveying the notion of desire to follow through with this act on someone else.
Guy 2: "Dude that is so nasty WTF?!"
He constantly fishes for comments and when someone sends him an ask he only posts the asks that give him attention like hate mail or making people feel bad for him.
"Let's get some Jam Jars, or play Bag Face"