UTG is huge fish, 90/30/9. Others are somehow decent regulars from vpip and pfr stats.

I obiously had an excellent hand and my betsizing was a little bit odd.
I expected that hand would become 3-way, regardless if I bet or not, but my hand would be more face up.

I decided to bet smaller, to avoid the annoying PSR where I feel committed and villains often hit better and stack me. So I wanted to bet a bit smaller and also hoped that fish would reraise with KKxx.

This is exactly the flop I hate with AA, especially 3-way. No glue how to play it. Against two opponents I don't feel like stacking off. I also hate to give free cards.

I also don't like to bet once and then give up and open great bluffing spots for villains. I probably would have folded to PSB and called 1/2 pots.

Was planning to check-fold

Here I got the blocker and I felt that the stab was somehow weak.
Problem was that the raiser was 90/30/9 fish. I suspected that he wont fold to small raise.

I know that my line is suspicious as with Aces with two diamonds I would have not played it that passively. I also suspected that fish won't think it that way.

I had no glue how 90/30/10 fish will think it in that spot. I expected to get called with K-high flush and maybe get folds from smaller ones. Though I have been called by sets too in similar spots. I find it difficult to decide whether this is a good move or just stupid way to loose much in the long run.