"My Home Hero" centers around Tetsuo Tosu, a middle-aged salaryman leading an ordinary life with his wife, Kasen, and their daughter, Reika. The family’s quiet existence is shattered when Reika becomes entangled with a violent yakuza member named Nobuto Matori. Concerned for his daughter’s safety, Tetsuo discovers that Nobuto has been physically abusing her. In a desperate attempt to protect Reika, Tetsuo confronts Nobuto, leading to a fatal altercation where Tetsuo accidentally kills him.

Faced with the immediate threat of yakuza retaliation, Tetsuo and Kasen decide to dispose of Nobuto’s body and cover up the crime. The couple’s meticulous planning and resourcefulness are put to the test as they navigate the dangerous underworld, constantly evading suspicion from both the yakuza and law enforcement. Their actions draw the attention of Nobuto’s associates, who begin to suspect foul play and launch an investigation into his disappearance.

As the story progresses, Tetsuo’s ordinary life unravels further, revealing his hidden intelligence and strategic thinking. Kasen, initially portrayed as a supportive but passive figure, demonstrates her own cunning and resilience, becoming an equal partner in their efforts to protect their family. The series delves into themes of morality, sacrifice, and the lengths to which ordinary people will go to safeguard their loved ones.

The tension escalates as the yakuza close in on the Tosu family, forcing Tetsuo and Kasen to make increasingly difficult decisions. Their struggle to maintain their facade of normalcy while outsmarting their pursuers forms the core of the narrative. The series balances moments of intense suspense with quieter, character-driven scenes that explore the emotional toll of their actions.

Throughout the story, the dynamics between Tetsuo, Kasen, and Reika are central, highlighting the strength of familial bonds in the face of extreme adversity. The narrative also introduces secondary characters, including yakuza enforcers and detectives, who add layers of complexity to the plot. "My Home Hero" presents a gripping tale of survival, blending psychological drama with crime thriller elements, as the Tosu family fights to outwit their enemies and preserve their fragile sense of security.