[Nick C]

It sounds like Villain has been 3-betting enough of your steals to make it suspicious, and as a result, you are in an awkward position versus this 3-bet.

If you just call, you're getting like 14:1 in implied odds, which sounds wonderful, except that I suspect you're frequently going to fall far short of stacking Villain when you flop a set. Meanwhile, you will often have the best hand with your unimproved 77 on the flop, but you won't know where you stand and will be in the unenviable position of basically playing chicken against an aggressive Villain without really knowing his postflop tendencies. I mean, if you call the flop, will he check the turn with his unpaired hands? If so, you can call the flop with the plan of betting if checked to on the turn and folding if Villain bets. But if Villain will two-barrel, then that plan sucks and basically amounts to letting Villain build a bigger pot for him to steal.

Your other options are to close your eyes and keep calling (playing for 130+ BB stacks if necessary so long as the board seems favorable) or to play back at Villain. The first option sounds really hazardous without a strong read that Villain is a bully who simply won't quit firing no matter what, and the second option amounts to playing chicken against an aggressive Villain you really only have a sketchy read on.

In the posted hand, probably I would call the flop bet, with the plan of reevaluating on the turn, but I wouldn't be happy about it.

4-betting preflop is another option and maybe a better one. I doubt you're much of a favorite versus Villain's range, since there are more PPs you're losing to than PPs you're beating and Villain will generally have two overs to your 77 when he doesn't have a PP, but chances are you have some folding equity, and the pot isn't empty. You're going to be repopping to like $20-22, though, so if Villain 5-bets you're either going to have to fold (probably the most sensible play) or you're going to end up calling and praying he just has AK. And, if called, you're going to be in an awkward spot on the flop.

It's a tough spot. I mean, you've got a good starting hand, but usually it's going to become marginal on the flop.