Villain completely unknown.

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

BB ($92)
UTG ($79.80)
MP ($50.75)
Hero (CO) ($50)
Button ($62.30)
SB ($49.60)

Preflop: Hero is CO with A, J
UTG calls $0.50, 1 fold, Hero bets $2.50, 2 folds, BB calls $2, 1 fold

Flop: ($5.75) A, 4, 7 (2 players)
BB checks, Hero bets $4.50, BB calls $4.50

Turn: ($14.75) 10 (2 players)
BB bets $12, hero ?