$100NL 6-max @ Tribeca
2 limpers. i raise OTB to $5 with [Js]. moron calls in SB. everyone else folds. he has $75 and i cover. his calling range OOP is literally any two cards. i estimate him at 75/25/2. he'll fire multiple streets with air, either as PF raiser or leading into the PF raiser. flop check is uncommon for him but not exceedingly rare.
flop: [4h][6h]
pot: $12
he checks. i bet $8. he calls.
turn:
pot: $28
check/check
river:
he thinks for 4 seconds and bets $32. my action?