A long time ago, Yashiro-Nene summoned the seventh of the school's seven mysteries, Hanako-san, and somehow, as time went by, they became friends. On the other hand, a boy named Minamoto-Kou, who was from a clan tasked with hunting mysteries, also became friends with them later. Even though he does not like Hanako very much, he does not see him as a threat, and also friends with Hanako-san Yashiro and Kou were in class, trying to pay attention even though they were bored.