First i must say great sprite work and presentation. The camera zooming out and zooming in is a little detail but adds so much to game fell :D The idea is simple but fun to play with. Maybe reduce the coil a little bit so its easier to hit enemies.
Unfortunately with games that control 2 characters at the same time comes with hard controls :/ Some times i was confused witch character was controlled by witch input. Also without sound effects the game feels unresponsive.
Other than that the base game is ready you should definetly develop this idea to its limit. I want to see this game in its full potential :D
Overall i liked the game great work :D