KK against mega NIT.

PokerStars No-Limit Hold'em, $0.50 BB (9 handed) Hand History Converter Tool from FlopTurnRiver.com (Format: FlopTurnRiver)

Button ($26.65)
SB ($57.90)
BB ($53.90)
Hero ($77.95)
UTG+1 ($46.60)
MP1 ($56.60)
MP2 ($49.30)
MP3 ($14.30)
CO ($60.40)

Preflop: Hero is UTG with K, K.
Hero raises to $2, 2 folds, MP2 raises to $6, 5 folds, Hero calls $4.

Flop: ($12.75) 7, 5, 6 (2 players)
Hero checks, MP2 bets $8, Hero raises to $22, MP2 raises to $43.3, Hero calls $21.30.

MP2 is 14/4 over 250+ hands.... I'm running 20/9. His 3bet range has to be QQ+, maybe JJ but that's doubtful, he is not the kind of person to make moves. He is one of those extreme nitty regulars. Now is this is bad line against his range? I am going to get all of his chips if he has QQ, and he will get mine if he has AA... Does anyone slow down against this guy, or consider folding after 3bet on the flop? This was a tough one for me...

id have 3 bet to 15-18 folded to a push unless youve seen him push QQ preflop (or think he might)
Losing $15 here to a preflop push wouldnt have been so bad imo.

i check call the flop, lead bet the turn and fold to a raise

How much do you lead the turn for?

the absolute number that allows me to get away from the hand if he raises, but a big enough number so it doesn't look like a block bet