I'm not sure, it seemed like the king had two other moves left...Maybe the opponent resigned?
Game Analysis: other vs. me
Well first you sacrificed your pawns to bring out your knights, then you brought out your black square bishop, then you and the enemy began preparing for the clash where the white's furthest pawn was, then once the king castled you and him began swapping pieces there, then you went to attack his queen, and I guess he decided to give it up for your rook or just messed up thinking of a different idea and forgetting about your rook...Pretty much it seemed to me that the enemy kept piece swapping when he/she was at a disadvantage for it, so you managed to take out his/her pieces, then you were able to corner the king since it was trapped by its castling move earlier.
All in all, you played the better game.
I somehow managed to win this game, and want further insight into how. Please help!