Masaomi Asahina, the eldest of the 13 Asahina brothers, is a calm and nurturing pediatrician who took on a fatherly role after their father’s death, especially for his youngest brother, Wataru. Though successful in his career, Masaomi struggles with insecurities and a fear of blood. His gentle nature and sense of responsibility define him. He prefers peaceful environments and is highly adaptable in caring for both family and patients, always striving to support those he loves.