Nice game. I loved the style and the idea of collecting souls for contracts was great.
I agree with some other comments that the attack speed, and the monster speed at the start of the game was off balance and made it feel a little too hard. I think the best advice I was given, especially for game jam games, is if you the designer think it's easy, make it easier.
But, once I figured out the technique, I had a lot of fun completing contracts and upgrading my player.
Really great potential, I hope you keep working on it.
D