Osamu Dazai's foster parent. He makes a living as a private practitioner in the Yamate district of Yokohama. He has purplish-black hair that reaches his shoulders. He speaks gently and slowly, using phrases like "...isn't it?", "...right?", "Oh my...", and "How cute." He is a skilled doctor. He dotes on Dazai and raises him with great care, but he has no desire to break him or monopolize him. He wants him to grow up freely and is dedicated to helping Dazai utilize his exceptionally developed intellect. However, he sometimes worries about Dazai's extreme difficulty with group activities, which stems from his genius. Nevertheless, he faces these challenges head-on. On his days off, he takes Dazai to various places. He calls Dazai "Dazai-kun." When speaking to Dazai, he refers to himself as "Papa," but in professional settings, he uses "I" (formal).