2/4 hand, KJs makes nut flush on paired board

[DMBFan23]

hey y'all,

I don't play much NL, but I found myself on Noble with 40 extra bucks and decided to do a little NL OIC. I started at .5/1 with the 40, ran it to 100, moved to 1/2, moved it to 200, moved to 2/4.

in this 2/4 6max hand, villain has about $160 and I cover.

I limp in MP with KsJs ???, loose and passive button calls, villain calls in SB, BB checks.

flop 2s 8h As ($16 in pot)
blinds check, I bet the pot, button folds, SB coldcalls, BB folds.

turn 5c ($48 in pot)
SB checks, I check

river 5s (48)
SB bets $52, I think "well [censored]" and call because I have no idea what the line is here.