Harumi Sakamoto is a supporting character from the anime and manga series Princess Princess. He is the eldest son of the Sakamoto family and the older brother of Akira Sakamoto, the protagonist of the related manga Family Complex. Harumi is a former student of the prestigious Fujimori Academy, where he was known by the admiring title of Sakamoto-sama due to his exceptional and striking beauty. He has black eyes and black hair cut to chin length, and his appearance is often described as being so perfect that he could easily work as a model.

In terms of his personal background, Harumi is a university student studying medicine. Despite his glamorous and somewhat dramatic personal style, his outward demeanor is typically calm, cool, and collected, with a frequent, gentle smile. However, this composed exterior is a stark contrast to his most defining personality trait: an extreme, emotional attachment to his younger brother, Akira. While normally reserved, the mere presence of his brother causes Harumi to become incredibly sentimental, easily moved to tears, and highly excitable. This intense reaction can be triggered even when witnessing circumstances involving Akira from a distance, leading to sudden and dramatic emotional outbursts.

Within the narrative of Princess Princess, Harumi appears as a minor but memorable guest. He returns to Fujimori Academy during the cultural festival to support the student council and assist with their fundraising efforts. His role primarily highlights the legacy of the school and provides a moment of interaction with the main characters, including the current "princesses" like Tooru Kouno and Yuujirou Shihoudani. His relationships are central to his character, defined almost entirely by his family, particularly his fixation on Akira. According to information from the prequel series Family Complex, his striking and feminine beauty ironically creates difficulties for him in romantic relationships with girls, who may be intimidated, while he enjoys immense popularity with his male peers at school.

Harumi experiences no significant character development within Princess Princess itself, serving instead as a static figure whose dramatic personality provides a specific contrast to his usual elegance. His notable abilities are not physical or combat-related but social; his beauty commands respect and admiration from almost everyone he meets. He also possesses a unique skill for swiftly transitioning from a sophisticated, princely individual into a weeping, overly affectionate older brother, a transformation that often surprises those who witness it for the first time.