Thank you for telling of these origins to your characters. It's interesting to read of how they started, developed and where you might want to take them.
Wouldn't say that Ams and and Ems are like God and Devil, that'd imply one is wholly good and the other's wholly evil.
I get the feeling they'rem ore two sides of the same coin that have their own presence, their own strengths and weaknesses and ways in which they could act or react in a given situation.
I remember when we talked some weeks agou about the opposite of someone's characters where you said something about Kinbari's uncaringness towards herself and others alike. Seems like out of these four, that character is on your mind the most with possible stories or things to discover.
The idea for Boxanne's head and the powers made me think a bit of Rayman 3 with the power washing detergents that could transform anyone's clothing into combat fatigues for a short while. I like the best ending idea too.
Time constraints aside, i hope making that game was fun and interesting for you.
Fair on keeping Nora simple and quite smart on having any situation she could be in, be part of a movie.