The premise reminds me of the Calvin and Hobbes comic where Calvin makes multiple other Calvins. While that comic plays it for laughs, this one takes a more introspective look at what it would be like to have another "self" with you.

At first the main character really enjoys having 2 selves. I mean, who is easier to get along with than yourself? Gradually she reveals more about her past though, especially regarding her sister, and things start to take a more sinister turn. The story has some great potential here, and I'll keeping with it for now. The art is fairly simple and typical, but works well with the story.