- Kokoro Onda (Nao Matsushita) is a medical oncologist. She decided to become a doctor to save people. After she graduated from medical school, she began to work in the radiology department. Working there, she saved a cancer patient through diagnostic imaging. This led her to pursue the field of oncology. She transferred to the tumor internal medicine department.
Kokoro Onda is dedicated to her patients. She meets surgeon Kaoru Kajiyama (Yoshino Kimura), who specializes in gastroenterology. Kaoru Kajiyama was recently transferred to the hospital where Kokoro Onda works. The two women begin to work as colleagues and also become friends.