Villian is 15/8. I've been very aggressive and he hasn't been stealing much so I did not 3-bet him preflop. $100 stacks.

1. Folds to villian on the button, he raises to $4, I call with [8s] in the sb.
2. Flop [Js][4d], pot $8. I check and villian checks.
3. Turn , pot $8 I lead $7 and villian calls.
4. River , pot $22. Hero does what?

I really doubt somewhat that nitty checks behind with the goods on the flop, but who knows. Am I better off check/calling or blocking here?

I'm guessing check/calling, though I could be wrong. If that's the case, how much am I willing to go up to? What do I do if he fires $22? $28?

15/8 villain will not have 65 here like ever.

No I'm not. If it were like 15/12 then sure. But 15/8?