bluffing missed draw

.25/.50 ring game.
This was my first orbit. People are generally weak/passive on these tables.

Hero (on the button): A [img]/images/graemlins/diamond.gif[/img], 2 [img]/images/graemlins/diamond.gif[/img]

Flop (Board: 10 [img]/images/graemlins/heart.gif[/img], 8 [img]/images/graemlins/diamond.gif[/img], K [img]/images/graemlins/diamond.gif[/img]):
Nyanyo: Bet 0.50
clabber: Raise 1.00
Hero: Call 1.00
Nyanyo: Raise 1.50
clabber: Call 1.50
Hero: Call 1.50 (I love those gayraises..........)

Turn (Board: 10 [img]/images/graemlins/heart.gif[/img], 8 [img]/images/graemlins/diamond.gif[/img], K [img]/images/graemlins/diamond.gif[/img], Q [img]/images/graemlins/spade.gif[/img]):

Nyanyo: Bet 3.00
clabber: Call 3.00
Hero: Call 3.00

River (Board: 10 [img]/images/graemlins/heart.gif[/img], 8 [img]/images/graemlins/diamond.gif[/img], K [img]/images/graemlins/diamond.gif[/img], Q [img]/images/graemlins/spade.gif[/img], 9 [img]/images/graemlins/heart.gif[/img]):
Nyanyo: Check
clabber: Check
Hero: Bet 6.50

the pot was 15 or so if I recall correctly, so I figured this play has to work just 1/3 of the time right ? I usually nut peddle on these tables so I'm not use to making these kind of moves, but they showed a lot of weakness on the river.