<Dt> Shiro (シロ) </Dt> <Dd> Voiced by: Ryōta Takeuchi (TV anime), Mitsuaki Madono (Yanagisawa) (Japanese); J. Michael Tatum (English) </Dd> <Dd> Actor portrayal: Hiroki Narimiya </Dd> <Dd> A mysterious scientist who cloaks himself in anti-sensei material, he first appears as Itona's guardian and tutor, bestowing him with the tentacles on his head and providing him the medication needed to treat it . After several failed attempts however, he abandons Itona, soon taking an interest in Kaede's potential . Once Kaede fails as well, he reveals himself as Kōtarō Yanagisawa, the lead scientist who performed the experiments that transformed the God of Death into Koro - sensei and destroyed the moon, thus making him the primary antagonist of the series . He also was Aguri's fianceé, and always mistreated her due to her low birth in comparison to his wealthy and well - connected family . He holds a grudge against Koro - sensei, who completely shattered his pride upon taking control of the experiment and winning Aguri's favor . He later returns after taking the second God of Death under his guard and modifying his body for them to enact revenge of Koro - sensei together in the final hour of the deadline before his explosion . Yanagisawa's body ends up severely damaged when he is blown away by a beam fired by Koro - sensei against the Second God of Death and comes in contact with an anti-tentacle barrier originally set up to trap Koro - sensei, leaving him in a semi-vegetative state . </Dd>

How old are the characters in assassination classroom