Sat down two hands ago just seen villain limp a couple of pots so I assume he's a fish and bad. His line here looks just very weird. Do you raise river or just call?

€€** Game ID 1962063875 starting - 2008-04-11 22:49:00
** Mosegi [Hold 'em] (0.50|1.00 NL - $ Cash Game) Real Money

- x sitting in seat 1 with $16.00
- hero sitting in seat 2 with $98.50 [Dealer]
- villain sitting in seat 3 with $105.67
- x sitting in seat 4 with $105.04
- x sitting in seat 5 with $102.68
- x sitting in seat 6 with $104.45

villain posted the small blind - $0.50
x posted the big blind - $1.00
** Dealing card to hero: 9, Q
x folded
x folded
x folded
hero raised - $4.00
villain called - $4.00
x folded

** Dealing the flop: J, 9, 2
villain checked
hero bet - $7.00
villain called - $7.00

** Dealing the turn: 9
villain checked
hero bet - $16.00
villain called - $16.00

** Dealing the river: 4
villain bet - $15.00

raise this 100% of the time, quite small though, around $39

I'd raise. I think he'll talk himself into a call quite often ("HAY, i induced imo")