Kotaro Yanagisawa Husbando

Kotaro Yanagisawa initially known as Shiro, is a mysterious scientist responsible for creating the tentacles, which establishes him as the main antagonist of the series. Once a proud scientist, Shiro wants to kill Korosensei for taking advantage of his experiments and ruining his life two years ago. Shiro is an influential character, as the repercussions of his research make him both directly and indirectly responsible for many major events, including the destruction of the moon and the creation of Korosensei. During his first appearance, he seems funny and easygoing, although it soon becomes clear that he is conniving, manipulative, and ruthless in his ambitions. Furthermore, he sees practically everyone other than himself as disposable. While in costume, Shiro wears white robes and a mask over his face, all made from anti-sensei fibers. Additionally, the back of his torso is adorned with a Bohr model of the hydrogen atom. Shiro also utilizes a voice modifier to further hide his identity from Korosensei. When unmasked, Yanagisawa has short, wavy dark green hair and pale teal eyes, along with fair skin.