Shiba Tonomo was a Japanese samurai from the Aizu domain of the Tokugawa shogunate. He was the father of Shiba Atsuko and Shiba Ibuka, both of whom fought in the Boshin War to preserve the traditions of the samurai against the Templar-backed Imperial Court of Kyoto. Tonomo trained his children in the ways of the samurai even though he expected that only his son would become a warrior like him while his daughter would simply be a good wife for a nobleman-in-waiting. Unbeknownst to Tonomo, Atsuko later disguised herself as a male soldier in an ashigaru battalion to watch over Ibuka. Neither was he aware that they were involved in an incident in which bandits attempted to rob his children only to be killed by Atsuko.
Tonomo participated in the Battle of Toba–Fushimi, but he was slain. His death led to Atsuko and Ibuka severing their bonds until the Battle of Aizu where the latter perished in the midst of carrying his sister away from the battlefield.