SB is 24/17, so not particularly tight, but importantly hasn't 3bet or 4bet once yet (79 hands, 22 opportunities to 3bet).

Three factors other than this make me want to fold:

1. The HJ is a big drooler (55/19) and if SB knows it, he's not likely to be expecting folds.

2. The SB has sized such that I can't close the action, because the HJ will (and does) shove for his remaining 2.5bb. Whether this is accidental or not is obviously impossible to say, but in any case is does prevent me calling without the risk that the SB repops it again.

3. SB and I are 185bb deep together. Even if I flat and the SB doesn't repop it, the SPR is going to be about 2, so I'm probably going to have to stack off on the flop with anything half decent.

Am I being too nitty, or do you like a fold?

Poker Stars, $0.05/$0.10 No Limit Hold'em Cash, 6 Players
Poker Tools Powered By Holdem Manager - The Ultimate Poker Software Suite.

Hero (BTN): $19.25 (192.5 bb)
SB: $18.68 (186.8 bb)
BB: $8.29 (82.9 bb)
UTG: $10.42 (104.2 bb)
MP: $2.75 (27.5 bb)
CO: $10.02 (100.2 bb)

Preflop: Hero is BTN with K A
UTG folds, MP raises to $0.30, CO folds, Hero raises to $0.90, SB raises to $2.50, BB folds, MP raises to $2.75 and is all-in