Ranma Saotome is the sixteen-year-old protagonist of the story and the only child of Genma Saotome and Nodoka Saotome. He is the heir to the Saotome branch of the Anything Goes Martial Arts school. Because his father took him away on rigorous training journeys when he was very young to raise him as a martial artist, Ranma does not remember his mother. During one of their final training trips, father and son traveled to the cursed springs of Jusenkyo in China, where Ranma fell into the Spring of the Drowned Girl. As a result, he is cursed to transform into a girl whenever he is splashed with cold water, while hot water returns him to his male form. After the accident, he and his father move in with the Tendo family in Nerima, Tokyo, and Ranma is introduced to the arrangement that has him engaged to one of the Tendo daughters, eventually leaving him betrothed to the youngest, Akane Tendo.

Ranma has a contradictory personality that mixes confidence, pride, and competitiveness with sensitivity and thoughtfulness. He can be brash, sarcastic, and quick to tease others, particularly Akane, yet he also shows genuine care, courage, and a strong sense of honor when situations become serious. He dislikes admitting his own feelings and often reacts with embarrassment or denial when his emotions are exposed. He is stubborn and dislikes losing, and he tends to react strongly to insults or challenges to his pride. At the same time, he is frequently indecisive and picky about personal matters, and he avoids openly confronting his own emotional attachments. While he generally identifies as a boy and dislikes being turned into a girl, he adapts quickly to the awkward situations created by his curse and remains resourceful under pressure.

His central motivation throughout the OVA stories is to find a way to lift the Jusenkyo curse and return to being a normal teenage boy. This goal repeatedly draws him into new martial arts challenges, magical encounters, and disputes with the many rivals and romantic interests who surround him. Beyond curing himself, he is driven by his desire to protect his reputation as a strong martial artist, to prove himself in combat, and to uphold the values of his training. He is also motivated by his deepening though unspoken attachment to Akane, and he frequently goes out of his way to help her despite their constant bickering.

As the central character of the story, Ranma is the figure around whom most conflicts form. The OVA episodes follow his continued search for a cure while he becomes entangled in chaotic situations involving his father, the Tendo family, his rivals, and the various people who pursue him as a fiancé. Although he often finds himself caught between the schemes of others, he is generally the decisive fighter and problem solver of the group, facing each new opponent with skill and determination. He enrolls at Furinkan High School and regularly becomes involved in martial arts contests and supernatural incidents that push his abilities to their limits.

His key relationships are marked by both affection and conflict. His engagement to Akane Tendo is the emotional center of the story; the two constantly argue and insult each other, but they repeatedly rescue, defend, and protect one another, gradually developing mutual respect and concealed romantic feelings. His father Genma is both his training partner and a frequent source of trouble, as Genma’s cowardice, scheming, and past promises create many of Ranma’s problems, including his mother Nodoka’s expectation that Ranma become a true man among men. Ranma is also entangled with several other fiancées against his will. Shampoo is a Chinese Amazon martial artist who, following the customs of her village, considers Ranma her husband after he defeated her, and she chases him relentlessly. Ukyo Kuonji is a childhood friend and okonomiyaki chef who was once promised to him as a child and remains attached to him in adulthood. His rival Ryoga Hibiki is cursed to become a small black piglet when splashed with cold water and competes with Ranma for Akane’s affections. Tatewaki Kuno is a boastful student who pursues Akane while also falling in love with Ranma’s female form without realizing the two are the same person. Ranma also deals with the elder Cologne of the Chinese Amazons, who sometimes mentors him and sometimes manipulates him, and with the elderly grandmaster Happosai, whose meddling frequently causes him grief.

Over the course of the story, Ranma shows meaningful development despite the mostly episodic nature of the plots. His feelings for Akane gradually deepen, and he becomes more willing to act on her behalf, even as he continues to deny how much she means to him. He learns to handle his curse and the constant interference of others with greater maturity, and his encounters with powerful opponents teach him both new techniques and lessons about himself. His pride remains a defining trait, but he slowly becomes more considerate and more capable of acknowledging the people closest to him.

Ranma is an exceptionally gifted martial artist trained from childhood in Anything Goes Martial Arts, a style that incorporates techniques from many disciplines and allows for improvisation. He has a remarkable ability to learn new fighting styles and techniques quickly, often mastering moves after seeing them only once or after intense training. Among his notable techniques are the Kachu Tenshin Amaguriken, a rapid-fire punching method learned through a dangerous training exercise involving roasting chestnuts, the Hiryu Shoten Ha, a countering technique that uses the clash of hot and cold combat auras to create a massive tornado, and the Moko Takabisha, a self-invented blast of energy fueled by his own self-confidence, created to counter Ryoga’s techniques. He also underwent the Neko Ken training as a child, which left him with a deep fear of cats even as it granted him the dangerous feline fighting state that emerges when that fear is triggered. While in his female form, his physical strength is reduced compared to his male body, but his agility and speed increase. His curse is also a practical weakness, as cold water can transform him at any moment and leave him vulnerable mid-fight, but he regularly compensates through quick thinking and adaptability, making him one of the most capable fighters in his world.