So, I don't think I have seen a game like this before, let me know if I'm wrong...
So! This is a user above you game. Let's say xyz said the object computer. I would then make the computer evil or demented, e. g. the computer now has fangs and uses them on a daily basis. I would then choose a new object.
Steel strings are all I need to say for once you play your mind will sway
Now thing onto a more serious tone, umm, it makes a irritating and horrendous noise every time something touches it, anything literally... Not sure if that's demented enough though. -- Looked on dictionary.com and seems that if used as a verb it means "to make mad or insane.".
What you perceive to be a harmless video game is actually you controlling a killbot somewhere in the real world, and every time you kill someone in the game, you actually kill them in real life.
It's possessed by soul of an ancient AG user who had been banned because of nothing. So the only thing that the soul knows is grudge and vengeance and the bunny will hunt and kill AG users one by one! Beware of bunny!!!