Entaro Hojo is Shusaku Hojo's father and Suzu Urano's father-in-law following her marriage into the Hojo family. Residing in the naval port city of Kure near Hiroshima during the 1930s and 1940s, he works as an aircraft engine engineer at Hiro Naval Arsenal. This role places him at a vital industrial facility actively supporting Imperial Japan's war effort, making it a frequent target for Allied bombings as the Pacific War escalates.

After air raids strike Kure and the Hiro Naval Arsenal, Entaro is reported missing, causing deep family distress. He is later found alive, sustaining injuries, and recovers at Kure Naval Hospital. Within his household, Entaro maintains a reserved yet stable presence. He is married to San Hojo, who lives with a leg injury, and their adult daughter, the widowed Keiko Kuromura, returns home after difficulties with her late husband's family.

Entaro's demeanor is consistently calm, composed, and serious; he rarely loses his temper. His interactions with Suzu lack the harshness sometimes associated with patriarchal figures of that era in arranged marriages. His character portrayal—defined by professional dedication, quiet resilience, and familial loyalty—remains consistent across the original manga, the 2016 animated film, its 2019 extended version, the 2011 television special, and the 2018 live-action series, without significant alteration or new backstory.