Opponent is a complete unknown.

PokerStars No-Limit Hold'em, $0.25 BB (5 handed) Hand History Converter Tool from FlopTurnRiver.com (Format: FlopTurnRiver)

Button ($10.05)
SB ($27.50)
BB ($26.15)
UTG ($20.50)
Hero ($27.75)

Preflop: Hero is MP with K, Q.
1 fold, Hero raises to $1, 2 folds, BB calls $0.75.

Flop: ($2.10) K, 4, 7 (2 players)
BB checks, Hero bets $1.5, BB calls $1.50.

Turn: ($5.10) 8 (2 players)
BB checks, Hero bets $3.5, BB calls $3.50.

River: ($12.10) 9 (2 players)
BB checks, Hero