25NL anonymous players. CO has $3.24. Hero and SB $32.50.

Hero gets JsJc on the BTN.
CO bets $.75
Hero bets $3.30
SB calls
CO calls off his stack.

Flop comes 9c9h6c. Pot size $10. $29 remaining.
SB bets $.25.
Hero raises to $6.75.
SB shoves all in
??

we have an overpair in a low SPR pot. Can we find the fold?
We get value from 10s basically only. The fact that the CO is also all in makes me think it less likely SB would do this with AK, and would be more inclined to do it with an already made hand to win everything. So while we get value from 10s and lose to Qs, I also think KK and AA are often in our opponents range and may have just wanted to let the CO call my 3bet.

It is true that AA, KK, QQ could have slow played you, it would be a good spot to but the sizing of the bet is odd. Seems fishy with the bet sizing, I could see him showing up with a few club draws with over cards, and small pairs. We flip against over card clubs, and have a small pairs crushed. Would be nice to have more information but would call.

Depends is SB is competent. If he is he should NEVER bluff here because there is no value in it. yes he get pick up your $6 but the fact that CO is in the hand changes thinks a lot. take out all bluffs and run he value range vs JJ and see if your ahead