canterbury bluff spot

[ship it pls]

8-16 canterbury

preflop: 3 limps from weak players in mid, fairly straight forward but slightly frustrated CO raises, hero calls AhQc in sb, bb folds, all rest call

flop: Jh 8h 6s - checked to CO who bets, 4 call (including me), 1 fold
(peeling is not standard here, but he checks behind a lot on the turn)
turn: 5d - checks to CO who checks
river: 7h - checks to CO who bets

i assumed i was done with the hand until it checked around to the CO... what are opininons on a c/r here? we are getting 4:1 on the play...