Shirosawa Takuya♂

Takuya is in his 6th year of medical school and just started practicing at the hospital to become an independent pediatrician. As soon as he arrives in the hospital hall, he sees a crying little girl so he decides to see if she's fine. Arrived at the girl, Takuya suddenly meets a young nurse about his age who has also come to see the little girl. After osculating the girl, Takuya realizes that the young nurse is not unfamiliar to him at all because she is in fact his childhood friend Mio with whom he spent all his youth and adolescence with.

After 6 years without seeing each other, Takuya and Mio renew their ties as soon as they have the time. One day, while they are talking up the stairs, a young boy jostles Mio who loses her balance. Takuya then grasps her hand and accompanies her in her fall, while protecting her in his arms and losing consciousness once down the stairs. He then wakes up in a hospital bed with the right arm and left leg broken. Feeling guilty, Mio asks him to ask her anything in exchange. Takuya then asks her if she can ask to take care of the room where he resides the time of his recovery.

His request being accepted, Mio and Takuya start together the adventure of their life.