villain is 18/15/2 over 80 hands. I dont know how often you guys call with 99 on this monotone flop(folding seems too weak). I just figure that my line might be too aggressive vs this passive player who might not stack off with his worse hands and probably only call with better stuff .

No-Limit Hold'em, $1.00 BB (8 handed) - Hold'em Manager Converter Tool from FlopTurnRiver.com

UTG ($109.55)
UTG+1 ($100)
MP1 ($100)
MP2 ($100)
CO ($109.20)
Hero (Button) ($107.95)
SB ($181.75)
BB ($100)

Preflop: Hero is Button with 9, 9
3 folds, MP2 bets $3.75, 1 fold, Hero calls $3.75, 2 folds

Flop: ($9) K, 3, 5 (2 players)
MP2 bets $6, Hero calls $6

Turn: ($21) 9 (2 players)
MP2 bets $15, Hero raises $39, MP2 calls $24

River: ($99) 7 (2 players)
MP2 checks, Hero bets $59.20 (All-In),