The call pre-flop is really loose. The 6 in your hand is almost completely useless, so you are effectively playing with a top gapped 3 card hand. Yuck!

The flop is decent for you, but not great. You have 7 nut outs and 7 non-nut flush outs if K-high is good. The call by the opponent in front of you likely means that some of your outs are either gone or will only be good for a split.

The turn bet by MP seems kind of weak, as is the call, especially given the draw heavy board and the fact that the idiot straight hit. Potting it here would be an interesting play, as you might be able to pick up the pot or at least force out the nut flush draw, thereby opening up a lot more potential outs for you. Anyways, I digress.

On the river, you hit the miracle card. A pot size bets puts your opponents all-in and is highly unlikely to be called. A weak bet, like 1/4 to 1/3 the pot might pull in a weak flush. That being said, a lot of it depends on what type of bet you usually try to steal with.

Just my 2 cents, which is probably worth a lot less than 2 cents.