A J Hartley 
Monsters in the Mirror [EPUB ebook] 

Darwen Arkwright’s world is turned upside down when he is forced to move from a small English town to Atlanta in the United States of America. Feeling out of place and struggling to fit in at school, Darwen seeks solace in a mysterious shop full of mirrors. It’s there that he discovers the ability to step through mirrors in to different worlds – worlds beyond his wildest imagination. Darwen befriends creatures including Moth, a tiny being with mechanical wings, but he soon learns that there is a terrible darkness threatening this new world…and only he can save it.The problem with doors is that they open both ways. There are monsters inside, and some of them are trying to get out…