Straight on river. Best line?
 

Party Poker, $0.10/$0.25 NL Hold'em Cash Game, 6 Players
LeggoPoker Hand History Converter

SS is a donkish idiot. He's been shoving every 2nd hand with any piece of the pot. No problem with calling the extra $1.63.

BB is relatively new. 63/5/1 (river AF=3 over 23hands).

Was this a bad river raise?

SB: $24.75
BB: $22.31
Hero (UTG): $31.95
MP: $25.99
CO: $6.88
BTN: $35.95

Pre-Flop: K[img]/images/graemlins/club.gif[/img] Q[img]/images/graemlins/diamond.gif[/img] dealt to Hero (UTG)
<font color="red">Hero raises to $1</font>, MP calls $1, CO calls $1, 2 folds, BB calls $0.75

Flop: ($4.10) 9[img]/images/graemlins/spade.gif[/img] 9[img]/images/graemlins/club.gif[/img] 3[img]/images/graemlins/club.gif[/img] (4 Players)
BB checks, Hero checks, MP checks, <font color="red">CO bets $0.25</font>, BB calls $0.25, Hero calls $0.25, MP calls $0.25

Turn: ($5.10) T[img]/images/graemlins/diamond.gif[/img] (4 Players)
BB checks, Hero checks, MP checks, CO checks

River: ($5.10) J[img]/images/graemlins/club.gif[/img] (4 Players)
<font color="red">BB bets $1</font>, <font color="red">Hero raises to $4</font>, MP folds, <font color="red">CO raises to $5.63 and is All-In</font>, BB folds, Hero calls $1.63

Re: Straight on river. Best line?
 

I think only hands which beat you call here

He surely has a flush here.