When the President got into an accident, Shirotani Tadaomi met Kurose. On their very first meeting, Kurose could tell right away that Shirotani is Mysophobic and said that it’s pretty bad while suggesting it would be better to consult a doctor about it. Shirotani was left perturbed by the encounter.
They meet again at the hospital, where Shirotani has decided to come for treatment. Shirotani finds that Kurose works there. Kurose offers to treat Shirotani if he would be his friend. Then, as part of the treatment, he tells Shirotani to jot down ten things he cannot do due to his phobia and number them from one to ten, ten being the action he finds most difficult to do. Shirotani does this, but leaves the tenth point blank. Later, when he asks Kurose why he is going to such lengths for him, Kurose says he would tell him once he filled in the tenth blank.
Thus they begin accomplishing the tasks together. However, Shirotani finds that he cannot do them with anyone else, and he insists that he isn't getting better. Their relationship becomes a physical one when Kurose confesses his love for Shirotani.