Seishirou is a character from the manga and anime series Tokyo Babylon and X/1999, created by CLAMP. He is known for his enigmatic personality and complex relationships, particularly with Sakura Kinomoto and Kamui Shirou. Seishirou is a skilled practitioner of onmyoudou, a form of traditional Japanese sorcery. In the series, Seishirou serves as a pivotal figure, often embodying themes of love, sacrifice, and fate. His character is marked by a duality, as he can be both a protector and a threat, making him a compelling and memorable part of the CLAMP universe.