A typical river situation that confuses me

[Harv72b]

Villain in this hand is a LAG fucktard over a small sample of observed hands (basically, this session + a couple orbits while I was waiting for a seat). He hasn't done anything truly maniacal yet, but he's definitely not afraid to throw chips into the pot, and he's definitely not good. I am just starting my second orbit at the table, and have only played one other hand (my first, when I wound up chopping a huge pot with AK vs. his K9 (the river double-paired the board)). So I don't have much of a table image, but what there is, is good.

Party Poker 5/10 Hold'em (9 handed) FTR converter on zerodivide.cx

Preflop: Hero is BB with 9[img]/images/graemlins/heart.gif[/img], 7[img]/images/graemlins/club.gif[/img].
<font color="#666666">7 folds</font>, SB completes, Hero checks.

Flop: (2 SB) 7[img]/images/graemlins/spade.gif[/img], Q[img]/images/graemlins/heart.gif[/img], 6[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(2 players)</font>
SB checks, <font color="#CC3333">Hero bets</font>, SB calls.

Turn: (2 BB) 9[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">SB bets</font>, <font color="#CC3333">Hero raises</font>, SB calls.

River: (6 BB) J[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">SB bets</font>, Hero...?

I'm obviously not folding, but do I raise or call?