Shiho Toono was a pediatric resident at a university hospital. Her forgetfulness and poor time management led to her making at least one mistake every day. Instructor Yamazaki frequently scolded her and finally snapped and told her to give up on being a pediatrician. After completing her residency the only place who would hire her was Sayama Clinic, a child psychiatry department in a rural area. Together with eccentric director Taku Sayama she will face various kinds of darkness within children's hearts.