Thin or too thin?

[recallme]

Villain is 50/22/1.5 and a donk. We have 100BB effective and i doubled him up 2 orbits earlier.

H has KK
2 folds, V calls, H raises to 90, 2 folds.

Flop: 5d2s7s
Villain c/c 170$

Turn: 4c
V c/c 380

River: 6h Pot is ~ 1300$ and ca 1250 behind
V checks, Hero?


I doubt he flopped a set or 2 pair on this flop, because he raised a flush AI with 30BB on flop.
He can show up with A7, here too.

Is this a easy check behind?