Unc:
A creepy, misbehaving, often drunk, uncle vibe having ne'er do well.
or
A close relative that is feeling themselves a little too much at the family gathering.
It really depends on context. The asshole that got balled up like used tissue after assaulting Congresswoman Omar was stumbling and smiling, then sprayed her with some fart spray or other childish prank. Another commenter called the assailant drunk. I just went with it.
Honestly that dude is lucky security got to him first, she was gonna whoop his stupid ass.