I really liked the premise of this game and the overall atmosphere of the game. I also liked the backgrounds and the sprites. The jumping isn't precise enough and having the high jump as "Enter" makes it feel awkward. Maybe, set it on the "S" key since it is on the same side of the keyboard. Also, I would make a square around the arrow so it's easier to telegraph the jumps. Natalya development was excellent but the rest of the characters felt a little flat in comparison. I think with some polish and fleshing out some more character details you could easily make this into a full game.