Kuniharu Saiki is the father of Kusuo Saiki, the protagonist of the series. He is a generally cheerful and energetic man in his mid‑forties, with a lean build, brown hair, and a face that often expresses exaggerated surprise or delight. He works as a salaryman but does not appear particularly ambitious or successful in his career.

In terms of personality, Kuniharu is kind‑hearted and deeply affectionate toward his family, especially his wife, Kurumi, and his two sons, Kusuo and Kusuke. However, he is also highly immature, prone to dramatic emotional outbursts, and easily excited or depressed by trivial matters. He has a tendency to act like a child, competing with his sons for his wife’s attention and reacting with jealousy when Kurumi praises anyone else. Despite his age, he often lacks common sense and practical judgment, frequently forgetting that his eldest son possesses overwhelming psychic powers. His reckless behavior and loud reactions sometimes put the family in awkward or dangerous situations, though he never intends harm.

Motivationally, Kuniharu wants to be a loving and fun father, but he is also driven by a simple desire for a comfortable, peaceful life with his family. He enjoys watching television, eating meals prepared by Kurumi, and spending time at home. He shows little interest in self‑improvement or professional advancement, preferring instead to indulge in hobbies and leisure. He does not seek to understand or control Kusuo’s powers; rather, he tends to ignore them in daily life, treating his son as an ordinary child unless a supernatural event directly intrudes.

In the story, Kuniharu serves as a source of comic relief and a counterbalance to Kusuo’s deadpan, weary perspective. While Kusuo is burdened by his abilities, Kuniharu remains oblivious or dismissive of the seriousness of those burdens. His carefree attitude often forces Kusuo to clean up after his father’s mistakes, such as when Kuniharu accidentally damages property or offends someone. Kuniharu’s lack of awareness about Kusuo’s powers also highlights the gap between Kusuo’s hidden life and his family’s ordinary expectations.

Key relationships define much of Kuniharu’s role. His marriage to Kurumi Saiki is loving but unbalanced; Kurumi is calm, practical, and the true authority in the household, while Kuniharu is emotionally dependent on her approval. With Kusuo, Kuniharu acts more like a playful older brother than an authority figure, frequently embarrassing his son with public affection or childish complaints. With the older son, Kusuke, Kuniharu is more intimidated, as Kusuke is a genius inventor who openly dismisses their father’s intellect. Kuniharu’s relationship with his younger son is warmer and simpler, though he often forgets that Kusuo’s psychic powers could solve mundane problems instantly.

Development is minimal across the series. Kuniharu remains consistently childish and loving, with no major character arc or dramatic change. The only notable shift is a gradual, grudging acceptance that Kusuo is exceptionally powerful, though this does not alter his behavior in any meaningful way. He learns minor lessons about responsibility occasionally, but these are quickly forgotten for the sake of comedy.

Notable abilities are almost nonexistent. Kuniharu possesses no psychic powers, special skills, or physical prowess. His only consistent “ability” is an uncanny luck in avoiding serious injury or consequence despite his reckless actions. He is also adept at cheering up his wife when she is upset, using humor and sincerity to defuse tension. Otherwise, he is an ordinary, unremarkable human whose main function is to provide a normal family dynamic against which Kusuo’s extraordinary life is contrasted.