CO is unknown. Might be weaker player.
When CO x back OTF, I don't see many Kx in his range, he might x sometimes KQ/KJ, even sets, but mostly I put him on A high, 87s/89s/54s/pp's.
OTT less Kx combos possible in his range if he x Kx OTF. So turn looks clear value bet. Should b bigger.
OTR his range IMO should be something like this( I don't know if he x Kx OTF or sets, but I put couple combos of Kx and sets):
Board: 8♦K♣4♠ K♠ 5♠
Equity Win Tie
MP2 50.00% 50.00% 0.00% { JdJs }
MP3 50.00% 50.00% 0.00% { TT-88, 55-44, KQs, 98s, 87s, AsQs, AsTs, KdQh }
A lot of assumptions made by me, but I think it's close spot OTR and without any reads x looks good, it would be easier If would bet OTT bigger.
Poker Stars $0.10/$0.25 No Limit Hold'em - 6 players - View hand 2670420
DeucesCracked Poker Videos Hand History Converter
Hero (SB): $62.03
BB: $25.92
UTG: $25.00
MP: $29.34
CO: $15.21
BTN: $79.53
Pre Flop: ($0.35) Hero is SB with J 
J 
1 fold, MP raises to $0.75, CO calls $0.75, 1 fold, Hero raises to $3, 2 folds, CO calls $2.25
Flop: ($7.00) 8 K 
4 (2 players)
Hero checks, CO checks
Turn: ($7.00) K (2 players)
Hero bets $3.39, CO calls $3.39
River: ($13.78) 5 (2 players)
Hero ???
