an expensive mistake on the turn?

[DiamondDave]

B&M 15/30, very good game.

Thirty-two players limp. I raise on the button with KsQs. The blinds call. Everyone calls.

The flop is 356 with two spades. The big blind bets, all 32 limpers call, I raise, everyone calls.

The turn is the ten of spades, giving me the second nuts. Everyone checks to the very loose player on my immediate right, who bets. I raise. Everyone folds, including the original bettor.

Who out there flat calls in this spot?