Ragyo Kiryuuin is the main antagonist of the anime Kill la Kill. She serves as the CEO of REVOCS Corporation, a global clothing distributor that dominates much of the world's apparel industry, and as the chairwoman of Honnouji Academy. She is also the head of the Kiryuuin family, the former wife of Soichiro Kiryuuin, who later operated under the name Isshin Matoi, and the mother of Satsuki Kiryuuin and Ryuko Matoi. Her background is deeply connected to alien organisms called Life Fibers. She discovered these fibers and worked to weave them into human clothing, with the larger goal of merging humanity with them. In pursuit of this goal, she conducted experiments on her own children, treating Ryuko as a failed subject and abandoning her, while raising Satsuki under her control. Scars across her back hint at a violent and bloody history tied to her involvement with the Life Fibers.

In personality, Ragyo carries herself with an air of luxury, elegance, and complete authority. She is vain and proud, openly flaunting her wealth, power, and status, and she regards herself as nearly divine, declaring that she is the light itself. She can be personable and even indulgent toward those who serve her loyally, but she is utterly ruthless toward anyone who opposes her. Her cruelty extends even to her family, as she shows no hesitation in harming, manipulating, or discarding people, including her own daughters, whenever it suits her purposes. Her worldview is built around the belief that clothing is the origin of civilization and that civilization is controlled by clothing, and she uses this ideology to justify her plan to remake humanity through Life Fibers.

Her central motivation is humanity's absorption into the Life Fibers, an outcome she pursues through her corporate empire and through the global spread of Life Fiber-infused garments. She seeks to awaken the Primordial Life Fiber and bring about the extinction of humanity as it exists, replacing it with a new form merged with the fibers. She believes this transformation is humanity's destined evolution and sees herself as the guiding force behind it.

Within the story, Ragyo initially operates from the background, appearing as a distant and mysterious authority figure before stepping forward as the true power behind the events of the series. She is revealed to be the mother of both Satsuki and Ryuko, and she becomes the primary obstacle that both daughters must confront. Her role shifts from a manipulative overseer to an active combatant in the final stages of the conflict, where she battles Satsuki and then faces Ryuko in a decisive confrontation. Her development follows a path from calculated, behind-the-scenes control to open confrontation, and her story ends when she chooses to take her own life rather than accept defeat.

In terms of abilities, Ragyo has mastery over Life Fibers and can control and merge with them at will. She possesses superhuman strength and durability, allowing her to survive injuries that would be fatal to ordinary humans and to regenerate from wounds, including impalement. She is also able to exercise mind control over people through Life Fiber-infused clothing, which serves as a key tool of her influence. Her most powerful form is the Shinra-Koketsu, an ultimate Life Fiber armor that grants her godlike combat capabilities. Combined with her intelligence, manipulative skill, and absolute control over her organization, these abilities make her one of the most dangerous figures in the story.