K - Season 2 Episode 13 Kings

Reisi and Mikoto continue their fight while Shiro tries to catch the Colorless King who's still in Kukuri's body. Helped by Kuro, who becomes his clansman, Shiro tricks the Colorless King to get out from Kukuri's body and trap him into his own body. Shiro teleports to where Mikoto and Reisi are and tells Mikoto to kill him while the Colorless King is still trapped in his body as only a king can slay another king. Mikoto does so, finally avenging Tatara's death but his Weismann level reaches its limit, which his Sword of Damocles is about to crash into the campus. Reisi is forced to kill Mikoto to prevent that which the latter shares some words with his fellow king before passing away peacefully. The Homra gang honors their late leader with a battle cry as they lose their powers. Neko and Kuroh escape the island, still believing Shiro is still alive.