Buso Renkin is a Japanese manga series created by Nobuhiro Watsuki. It follows the story of Kazuki Muto, a high school student who becomes involved in a battle against monstrous creatures known as Homunculi. After a fateful encounter, he receives a powerful alchemical weapon called a Buso Renkin to protect his loved ones. The series combines action, fantasy, and adventure elements, showcasing themes of friendship and sacrifice. Kazuki and his allies, including Tokiko Tsumura, fight to uncover the truth behind the Homunculi and the mysterious organization that controls them, all while navigating their own personal challenges.