Blind steal faces turn raise

[Zarl]

Party 2/4 full, no solid read on Villian because I just joined the table.

7 players fold to Hero on the button with A3o (suits unimportant), <font color="red">Hero raises</font>, SB folds, BB (Villain) calls.

Flop comes QQAr (2 players for 4.5 SBs)

Hero bets, Villain calls.

Turn is an off-suit K (2 players for 3.25 BBs)

Hero bets, <font color="red">Villain raises</font>, Hero...?

What do I do here? Why?