Hideji Saijo, the dedicated butler of the Hanawa family, is affectionately known by the nickname "Hide-Jii." He presents a distinguished appearance with grey hair, prominent bushy eyebrows, and a moustache, often seen wearing rimless spectacles featuring a black frame. His attire consistently consists of a black coat, formal black pants, a white shirt, a necktie, and black shoes.

Kindness, humility, and profound devotion define Hideji's personality, especially evident in his attentive care for Hanawa-kun. His hospitable and amiable nature garners admiration from Hanawa-kun, his friends, and others within their circle. His primary focus and talent lie in meticulously attending to Hanawa-kun's needs.

Relationships are central to his role. He maintains professional service to the Hanawa family while also interacting respectfully with Maruko's family and Hanawa-kun's classmates, consistently demonstrating his supportive character.

His preferred foods include gratin dishes and traditional Japanese cuisine. The character's name, "Saijo Hideji," draws partial inspiration from the real-life 1970s pop idol Hideki Saijo, known for songs such as the Japanese version of "YMCA," reflecting the series' use of Shōwa-era cultural references.