Stars 10NL midpair facing huge river overbet

[udbrky]

Villain is 77/19/4, goes to showdown 19%, winning 100% over just 30 hands.
PokerStars No-Limit Hold'em, $0.05 BB (6 handed) Poker Stars Converter Tool from FlopTurnRiver.com (Format: 2+2 Forums)

SB ($5.57)
Hero ($10.67)
UTG ($12.20)
MP ($6.16)
CO ($6.93)
Button ($9.15)

Preflop: Hero is BB with 7[img]/images/graemlins/heart.gif[/img], 8[img]/images/graemlins/spade.gif[/img].
<font color="#666666">2 folds</font>, <font color="#CC3333">CO raises to $0.1</font>, <font color="#666666">2 folds</font>, Hero calls $0.05.

Flop: ($0.22) T[img]/images/graemlins/club.gif[/img], 3[img]/images/graemlins/spade.gif[/img], 7[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(2 players)</font>
Hero checks, <font color="#CC3333">CO bets $0.1</font>, Hero calls $0.10.

I call thinking he's missed the flop and is making a weak bet. This was the whole reason I called isn't it? If not to exploit his tendencies, then why am I playing?

Turn: ($0.42) 6[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero bets $0.25</font>, CO calls $0.25.

He thinks for about 6-7 seconds before calling.

River: ($0.92) T[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
Hero checks, <font color="#CC3333">CO bets $2</font>, Hero thinks he's playing on a different table than villain?????

Final Pot: $0.92
What the faygo is the river bet?

These bets confuse me a lot.