15-30 deep against ansky

[PMP07]

Playing 4 handed with myself, Ansky, Aeron, and Samd. Game has been very aggressive with alot of 3 betting. Ansky has been at the table for about 3 orbits, and seems to be playing pretty standard. I have 6k, and ansky covers.

Folds to me in SB and I raise to 90 with KK. Ansky reraises to 270, and I 4-bet to 1k. He thinks for a bit and calls. Flop came 9 7 6, with two spades, and I c-bet 1450. Ansky shoves, and I make the call and lose to AA. Do you guys think this is just a standard stack off spot with KK, or is it possible to have gotten away from the hand? Ansky seems like a reasonable thinking player, and I'm pretty sure he knows that when I 4-bet I have a fairly strong hand. That being said, can I ever really fold KK here? I really doubt he would shove QQ/JJ here since we haven't been at the table very long together and neither of us has gotten out of line. All thoughts on hand appreciated