They become very furious when objects are taken away from them that are the right size for the arsehole.
Once furious, they tend to start to fist them selves resulting in shit everywhere.
Not only this, once in their furious state they start moving around very stiff and are thrusting their arms in a "rooting" mode. Treweek's tend to dribble alot once furious and can tend to crack teeth from clenching to hard.
Blaine; Fuckin Peter did a Treweek.
Benny; This turns me fucking on hard core SHIT