This is really cool game, I love this pixel art animations and music! I FCed (full combo) 3 times with empty boss health, 169 perfects and 10 or so "goods", but I guess its not enough to kill the boss...( sad...
Thank you for trying the game and your feedback ! Seems like i've got a bug in the game. You should have beat him if you got 161 perfects or more (90% perfect).