In the world of Maydare, where great magicians pull the strings of fate, there lived the "Scarlet Witch." She was condemned as the most wicked of them all. Makia is a descendant of that fabled "worst witch." Lately, Makia has been having dreams about a high school girl named Kazuha Oda... who turned out to be the person Makia was in her previous life! However, it so happened that Kazuha was murdered by a mysterious stranger...

Female college student Aoi inherited her deceased grandfather's ability to see ayakashi. One day, while Aoi is feeding some ayakashi, a demon appears! He declares that Aoi's grandfather owed a great debt, and as compensation, Aoi must marry the demon! Aoi refuses, and decides to pay off the debt by working at the inn of the afterlife, the Tenjin-ya.