(NL100) Standard or pretty weak?

[DawnToDusk]

Stats:
Hero 36/26/14 over 75
SB 26/9/1.25 over 70
CO 41/3/1 over 30

History:
The table started four handed and I was raising a ton on the CO and the button. I snapped off the SB pocket KK with 78o after he 3bet me on the button. I am sure he thinks I have a very wide raising range but he hasn't really played back since that hand. In fact it seems like I am able to pots off of him with CBets all the time now and pick up his limp calls.

CO is relatively unknown. I had played 20 hands with him previously but nothing special to note.

Absolute Poker
No Limit Holdem Ring game
Blinds: $0.50/$1
6 players
Converter

Stack sizes:
Hero: $201.85
UTG+1: $32.85
CO: $38.50
Button: $191.90
SB: $191.45
BB: $57.32

Pre-flop: (6 players) Hero is UTG with 9[img]/images/graemlins/heart.gif[/img] 9[img]/images/graemlins/spade.gif[/img]
<font color="#cc0000">Hero raises to $4</font>, UTG+1 folds, CO calls, Button folds, SB calls, BB folds.

Flop: 6[img]/images/graemlins/heart.gif[/img] 5[img]/images/graemlins/spade.gif[/img] 3[img]/images/graemlins/diamond.gif[/img] ($13, 3 players)
SB checks, <font color="#cc0000">Hero bets $8</font>, CO calls, <font color="#cc0000">SB raises to $16</font>, Hero folds, CO folds.
Uncalled bets: $8 returned to SB.

Results:
Final pot: $37

Am I just playing this hand too weak or is this pretty standard? I don't think the SB min-raises here with a draw and anything weaker than two pair. In fact I don't think he has a draw here ever I feel like the only hand I am beating is 77 and 88. I probably would of peeled another one off if the CO wasn't sitting behind me.

What do you do in this spot if there is no CO involved in the hand?