Gentoku Ryuubi is a character from the anime Ikki Tousen: Shūgaku Tōshi Keppu-roku, where she portrays the reincarnation of the legendary Three Kingdoms figure Liu Bei. Attending Seito Academy as a second-year student, she is a bespectacled young woman with a seemingly absent-minded and clumsy demeanor. Physically, she is noted to be 160 centimeters tall. Her personality stands in stark contrast to many of the more aggressive fighters in her world, as she is typically timid, carefree, and more interested in being a bookworm than a warrior, possessing no apparent combat skills under normal circumstances.

Despite her gentle and ditzy exterior, Gentoku is fated to be a great leader. Her primary motivation stems from her deep care for her friends, and it is in these moments of emotional distress that her true power emerges. She shares a particularly strong bond with her best friend, Chouhi Ekitoku, and is a close associate of fighters like Kanu Unchou and Ryomou Shimei. When she witnesses her friends being hurt in battle, her dormant power activates, causing highly destructive outbursts. This power comes from the dragon she harbors, known as Rairyuu, the Lightning Dragon. This dragon is described as being immensely evil, radiating entropic energy so potent that on a prior occasion, it nearly forced Gentoku to disembowel herself before her friends managed to stop her, suffering critical wounds in the process. Gentoku herself seems largely unaware of this terrifying potential within her.

Her role in the story focuses heavily on her personal struggle to master this inherited power. In the events preceding the anime, she was overwhelmed by her dragon in a major incident three years prior. The narrative follows her journey as she begins to slowly gain control over her dragon's abilities. A pivotal moment for her development is when her friend Kanu is forced to surrender to the rival fighter Sousou Moutoku. Gentoku's fierce determination to rescue Kanu becomes the catalyst that allows her to start controlling her dragon's strength. She eventually realizes that Seito must go into battle to finally end the ongoing conflict. During this critical fight, she becomes a target but manages to protect herself. After Kanu’s return, which gives her further encouragement, she faces Sousou directly. Though almost strangled, she is saved by Hakufu Sonsaku, and the two team up to destroy Sousou, securing victory for their alliance. Following this climactic battle, Gentoku returns to her normal, peaceful life as a bookworm, having demonstrated that she can rise to the occasion when her friends need her most.