When two doors are discovered in an ancient ruin, the gateways to Shinkai, the Realm of the Shinzoku (Gods) and Makai, the Realm of the Mazoku (Demons) are irreversibly opened. The races of human, shinzoku, and mazoku come together in the mortal world and nothing will ever be the same. One day, two new families move next door to a boy named [Tsuchimi Rin] who had previously been living a very peaceful life. In one house lives the family of the King of the Gods, and in the other lives the family of the King of the Demons. Both families have one daughter whose single wish is to live next to the boy they have fallen in love with years ago, their wishes have been fulfilled. Interestingly, living with the boy is his childhood friend. With these three girls vying for his affections, Rin finds that his new life will be all but peaceful