...and you know what happened.

Party Poker 0.15/0.30 Hold'em (9 handed)

Preflop: Hero is SB with , . UTG =#A500AF(Villian)/ posts a blind of $0.15. MP3 posts a blind of $0.22.
UTG =#A500AF(Villian)/ (poster) checks, UTG+1 calls, MP1 calls, 1 fold, MP3 (poster) checks, 1 fold, Hero raises, BB calls, UTG =#A500AF(Villian)/ calls, UTG+1 calls, MP1 calls, MP3 folds.

Flop: (11.46 SB) , , (6 players)
Hero bets, BB calls, Villian raises, UTG+1 folds, MP1 calls, Hero calls, BB calls.

Turn: (9.73 BB) (5 players)
Hero bets, BB raises, Villian 3-bets, MP1 folds, Hero caps, BB calls, Villian calls.

River: (21.73 BB) (4 players)
Hero checks, BB bets, Villian raises, Hero 3-bets, BB calls, Villian calls $0.60 (All-In), Hero calls, BB calls.

Final Pot: 33.73 BB

Given how many people at these levels play with any suited cards, I thought for sure that Villian had a lower flush.

When you were raised AND re-raised on the turn, you should have gone to call-down mode from there. It's obvious both of them have a flush. One of them are very likely to have the ace. This is NOT the place to be capping and 3-betting your 2nd best hand!

Do you really think they'd be raising AND re-raising with a T-high or J-high flush? They won't. Sure maybe one of them is a moron, but not two of them!

I might even fold the K-high flush to that action. It's far too obvious someone has the ace here.

i think you gotta muckit to a three bet, hands down. The funny part is the guy didnt cap the river because he probably thought there was a possibility you had the straight flush!

EDIT: Whoops NM villain was allin. yeah yeah, misreading posted hands is my specialty, as some of you might know.

The first example you posted in there were people betting, raising, and capping with a set and a straight. The second example, one of them was going crazy with the OESD, the other had top set.

Here, you have two people going bet-raise crazy on a four-to-a-flush board. With that much action on a four-to-a-flush on the turn AND river, I'm more than 95% certain your K-high flush is beat.

The majority of players are not maniacs. In fact, the majority of players are loose-passives. When you find maniacs, make note of them.

I thought the pot odds miscalculation could be a major leak in your play. My comment about the check-raise was cruel, I admit.