Navel - Shuffle!

One day, the worlds of "Gods" and "Demons" are connected to the human world by opening "The Gate" found at a particular archaeological site. Those two different worlds were ruled by "magical powers," which shocked humankind as supernatural things don't exist in the human realm.
Later, despite the twists and turns about the existence of the Gate, cultural exchanges with the three worlds proceed, and eventually, the three races and worlds coexist peacefully. Ten years had passed since then.

The story follows the life of Tsuchimi Rin, a student at Verbena Academy of the Koyo Town, where many humans, gods, and demons live. Rin soon discovers that his average daily lives will soon be changed by encountering the two princesses of the Devils and Gods who are looking for him.