Entarō Hōjō is the father of Shūsaku Hojo and father-in-law of Suzu Urano. He lives with his family in Kure, employed as an aircraft engine engineer at the Hiro Naval Arsenal. This work situates him within the military-industrial complex supporting Japan's naval forces during wartime. Entarō possesses a calm, composed, and serious nature, rarely showing overt emotional reactions, even under duress.

He serves as a steady patriarch. His wife, San Hojo, has a leg injury limiting her mobility, requiring household assistance; after her marriage, Suzu helps fulfill this need. Entarō maintains a respectful and accepting relationship with Suzu within the family structure. Despite growing danger from Allied air raids targeting Kure's naval facilities, Entarō persists in his work at the arsenal.

A significant air raid attack on the Hiro Naval Arsenal results in Entarō going missing, causing the family considerable distress. He is later found alive yet injured, receiving treatment at Kure Naval Hospital. His survival and recovery demonstrate resilience amid the widespread destruction affecting the city and its people.

Following Japan's surrender and the war's end, Entarō resumes his place within the family as they face the challenges of post-war reconstruction and life under American occupation.