Villain is TAG

PokerStars No-Limit Hold'em, $0.50 BB (6 handed) Poker-Stars Converter Tool from FlopTurnRiver.com (Format: FlopTurnRiver)

Button ($67)
SB ($60.50)
BB ($49.50)
UTG ($57.70)
Hero ($51.60)
CO ($48.20)

Preflop: Hero is MP with J, J.
1 fold, Hero raises to $2, CO calls $2, 3 folds.

Flop: ($4.75) 3, 4, 8 (2 players)
Hero bets $4, CO raises to $9