Shuffle!

The novel takes place in a made-up planet where races of gods and devils live side by side with mankind. Both races possess mystical abilities that humans found astounding because they had never experienced anything like it. Both sides are generally friendly despite their positive and negative perceptions. The portal between the godly and demonic realms was opened ten years prior to the events of the novel. Since that time, immigrants of all races have crossed the globe. National Verbena Academy in Ky-ch, a multiracial high school, is where the characters study. All of this is carried out in order to facilitate the harmonious coexistence of people, gods, and demons. Nevertheless, a few people from each species had managed to escape to one of the other worlds, where they were married and started families as a result of inexplicable dimensional tears. This explains how some mixed-blood students, like Mayumi Thyme, whose human parent entered the realm of the Devils through one of those tears years before the gateway to the Human world was opened, and Ama Shigure, Asa's mother, can be older than the opening of the portal to the Human world. She was somehow brought to the Human world from the Devil's realm.