A really fun and interesting concept for a game! I really really really love how the cutscenes look - the text bubbles fit in so well with the backing art! I also really love how many options there are for combos, and the drawn lines look excellent :D
I think my main critique for the game that I hope helps in the future is that the window to start a combo seems a little small. I found myself spamming the ctrl button to get the right time to draw symbols. Maybe the window could be a bit longer and if you miss, you have to wait a couple seconds to try again?
But yeah, I had a really great time playing, and I'm excited to see what else comes from this project. Congrats ya'll! :D