Queen's Quality 6

The members of the Horikita family have a strange profession: they are "cleaners" of the soul, meaning they rid people's hearts of impurities. Fumi begins helping them and moves into their home, where she is valued for her abilities. At a certain point, however, a mysterious power begins to awaken within her, making her a "Black Queen," a being capable of exerting enormous power over people! Realizing the power of the silver sea serpent, Kyutaro and Fumi have decided to undergo training with the old Byakko clan in order to improve their skills. Then Akiyama appears, who, in the guise of a messenger, tests Kyutaro with a spell! Fumi cannot bear to see her beloved suffer, but she does not know that Kyutaro is on the verge of losing his mind precisely because of his love for her. Has their story reached a turning point?