TP river, all draws arrived

Preflop: Hero is BB with T:s, 6:s.
UTG2 folds, MP1 raises, MP2 calls, 4 folds, Hero calls.

Flop: (6.5 SB) 6:c, 2:s, 3:c (3 players)
Hero checks, MP1 bets, MP2 calls, Hero raises, MP1 calls, MP2 folds.

Turn: (5.75 BB) 4:d (2 players)
Hero bets, MP1 calls.

River: (7.75 BB) 2:c (2 players)
Hero ?

Hi!

Opponents unknown.

What's better on the river? If he's reasonable than he understands that all draws arrived so if we bet he doesn't have to call it unless he has a flush & he would raise it. So his decision is fold or raise I believe. As he didn't show overpair earlier he has overcards but no calling range I think. And if we check than will he turn his overcards into bluff? Probably no... I can't figure out what's best on the river.