"Neko ni Tensei Shita Ojisan" centers on a middle-aged man who unexpectedly dies and reincarnates as a stray cat in his former neighborhood. The protagonist, now inhabiting the body of a cat, navigates his new life while observing the lives of those he once knew, including his estranged family and former colleagues. The narrative explores themes of regret, redemption, and the complexities of human relationships through the unique perspective of a feline.

The story begins with the protagonist’s sudden death, followed by his reincarnation as a cat. Initially disoriented, he gradually adapts to his new form, using his feline abilities to explore his old surroundings. His interactions with humans are limited by his inability to communicate verbally, but he gains insight into their lives by observing them from a distance. The protagonist’s former family, unaware of his true identity, becomes a focal point of the story. He witnesses their struggles and emotions, particularly those of his wife and daughter, who are coping with his death in different ways.

As the story progresses, the protagonist attempts to influence events subtly, using his cat form to provide comfort or intervene in small but meaningful ways. His actions often lead to moments of introspection, as he reflects on his past mistakes and missed opportunities. The series balances lighthearted moments, such as the protagonist’s humorous attempts to navigate life as a cat, with poignant scenes that delve into the emotional impact of his death on those he left behind.

The supporting characters include the protagonist’s wife, who is grappling with grief and financial difficulties, and his daughter, who struggles with feelings of abandonment. Other characters, such as neighbors and former coworkers, provide additional layers to the narrative, highlighting the interconnectedness of the community. The series also introduces other animals, particularly a fellow stray cat, who becomes a companion and offers a contrasting perspective on life.

The plot unfolds through a series of episodic events, each focusing on different aspects of the protagonist’s new existence and the lives of those around him. The narrative maintains a steady pace, blending slice-of-life elements with moments of emotional depth. The protagonist’s journey as a cat serves as a vehicle for exploring broader themes of mortality, forgiveness, and the enduring impact of one’s actions on others. The series concludes with a resolution that ties together the protagonist’s reflections and the changes he has witnessed in the lives of his loved ones.