Ooooofff!!! This is such a nice game!
I kinda desagree with some comments, its possible to play the game controlling both characters, tho the idea of a co-op (local or a fun adventure online!) sounds really nice! or maybe you can have the user decide if he wants to play with one character at once (and make this the easy level) and leave both characters at once for a challenging experience!
The important thing here, is that Its a beautiful game! The characters are intriguing and really well designed! The tutorial is clear enough and the game its pretty much inntuitive!
And the lighting! It adds so much to the scene and to the narrative.
What a great job!! :)