Villain seems to be a reg. Playing 20/18 on 248 hands. AF in general is 1,8.
Flop Agg % = 43
Turn Agg % = 41
River Agg % = 27

We're playing 3-way flop. It means our top pair loose some strenght compared to a HU flop.
I decided to check in order to take a two or one street of value.
Our hand is quite protected since the A is only bad card on turn.
By checking we decrease our fold equity which means we have more value to delayedCB other streets.

Okay.

Turn the villain overbets. I don't think it's a fold already.
River he bets around half pot. Can we fold our top two pair?
Even that the third diamond comes on the board, should we fold?
He is not betting big.
The only thing that concerns me is his low agg on the river and the overbet on the turn.