Mad Ass-Hatter

Mad Ass-Hatter is that one guy /girl who is absolutely batshit crazy and also an asshat/jackass.
Usually reserved for exes, enemies, or frenemies.

Can be used as an action word as well to describe weird situations/drama.

Example 1:

Person A: Dude, Jack is such a mad ass-hatter.
Person B: I know right? Can’t believe I dated that fucking psychopath.

Example 2:

Person A: Yo, did you just see what she did to George?
Person B: Yeah, that was some weird mad ass-hattery, my guy.