Sento Kiryu is the main protagonist of the tokusatsu series Kamen Rider Build. A brilliant physicist with a mysterious past, Sento takes on the identity of Kamen Rider Build to fight against the threats caused by the Pandora Box and the resulting Skywall Disaster in Japan. He is known for his intelligence, scientific curiosity, and strong sense of justice, often using his inventions and analytical skills to overcome obstacles. Sento's journey is central to the series' story and emotional core.