IMO the SB is super nutted and due to the flop play he knows where you are at as well which is why he leads turn again and then ships over your raise.  Its a cooler spot nonethless but I think his betting may have allowed you to get away from the hand or at least play it differently.  He could possibly have Kcx and is just willing to run it if hes a fish but realistically I think thats the only hand you are beating.  He has no sets and he does not have a straight either based on how the hand was played.  You beat any Kcx and  worse flushes but worse flush draws are pretty unlikely.  I think I like just calling flop and reevaluating the turn.  I try my best to not bloat pots unless if I have nutted hands pre ante period in tournaments.  Based on the flop play you now made the hand pretty tough to get away from.  I like to call the open and reevaluate turn.  If he barrels again I might just call all the way down that way you can keep all his Xc bricks in range as well.  He may think you are just chasing and barrel all three streets since you are only calling.  So now you are under repping your hand but at the same time you are controlling the pot.