Different

A young 18 year old named Andy has grown up in the famous city called heaven. That's all she has ever known in her life. Her family, friends, and home is there.
At 18 there is a test to determine the personality type and IQ of each person. If the person fails they are cast away from the city of heaven and have to leave to create a life out in the rest of the now empty world.
When she discovers a city full of others that were cast away she comes to like it there. She finds friends she now calls her family, and someone new she falls in love with. But when she finds out there is an enemy to her new city her life becomes terrifyig.