Lio Shirazumi, first appearing briefly in the second chapter/film of Kara no Kyoukai as an older schoolmate of Mikiya Kokutou who dropped out of school because he “found something he wanted to do”. He is later seen eating at a diner with Mikiya, in which they both bid each other farewell afterwards.
Lio is in actuality the true culprit behind the murders of 1995-1996, later appearing again as the main antagonist in the seventh chapter/film.
Lio initially stalked Shiki Ryougi, due to having a crush on her. Confessing his love for Shiki, he was rejected by her; in which she described him as a “weak person”. This led him to internalize Shiki’s words, deciding that he must prove his strength and worth by challenging a local school bully. The encounter resulted in Lio murdering and eating said bully after which Souren Araya approached him, desiring Lio’s consent to awaken his origin; with the promise that Lio would become a “transcendental man”. Since awakening his origin, Lio began a murderous campaign throughout 1995 up to 1996. Having psychologically manipulated Shiki into thinking that she is the murderer who was responsible for his crimes, the experience drove Shiki to nearly commit suicide; in which Araya halted Lio’s activities and deemed him a failure for causing issues in his plans.
Lio resumed his murders in 1999 after Araya’s death, in which he formed a cult-like drug trade and began distributing modified drugs soaked in his blood; hoping that it would help awaken other people’s origin in order to gain a murderous companion as a means of subconsciously sharing the burden of having a guilty mind. Lio mainly set his sights on Shiki and Mikiya, due to his love for Shiki and his past friendship with Mikiya. Lio would separately confront the two several times, in an attempt to convince them to join his side as fellow murderers. In the seventh chapter’s climax, Lio is rejected by both Shiki and Mikiya, in which Shiki killed Lio in a final battle under the assumption that Lio had truly murdered Mikiya.
Due to awakening his origin of “Consumption” (literally translated from “to eat”), this caused Lio’s body to mutate and gain superhuman reflexes with a cannibalistic instinct, resulting in him slowly losing his sanity in the process. Over the course of many years, his eyes became more reptilian/feline with a red-orange color, while his hair turned into golden blonde. In 1999 he’s shown to have developed retractable claws as well as implied to have gained the ability to regrow lost limbs.