NL$200| AQ (TPTK), unexpected river re-raise

[Acevader]

Table is Full Tilt 6-max (5 seated) NL$1/2

Villain is 33/20/4.5 (360)

I'm playing around 19/16/3 on this table.

I have $209, villain covers.

Sorry for the manual history on this occasion:

UTG raises to $7, all fold to hero on BB with AhQs.

Hero calls

I call here because I'm ahead of villains range but he's far too volatile to play OOP in 3-bet pots

Flop 9c,Qh,9s

Hero checks, UTG bets $8, hero calls.

Turn 7h

Hero checks, UTG checks

I was going for a check-raise for value here since villain would call it with QK/QJ and possibly under-pairs

River 6h

Hero bets $20

UTG raises to $90

Hero?????