Final Boss Time

Fighting on two fronts against the Reaper and Yanagisawa, Korosensei begins to buckle, and the punishment worsens when Yanagisawa turns the Reaper loose on the students. Dismissing the children as obstacles, Yanagisawa is met with Korosensei's insistence that they are the finest gift teaching ever gave him. In the chaos Kaede throws herself at the Reaper and is struck down, her fatal wound seeming to tip Korosensei into pure fury.

What looks like rage is actually every emotion at once flooding his face. Channeling it, Korosensei unleashes a massive burst of energy that blinds the Reaper and hurls Yanagisawa into the very laser barrier meant to trap him, killing him instantly. He then drives a killing blow into the Reaper, the man who had only ever wanted his teacher's approval. Having carefully shielded Kaede's spilled blood throughout the battle, Korosensei uses his abilities to close her wound and pull her back from the brink of death.

The episode debuted in Japan on June 16, 2016, adapting Chapter 172 through Chapter 175. Compared with the manga, the anime keeps Korosensei's face steady rather than cycling through expressions as he charges the beam, and the cake survives with less soil damage, so during the impromptu surgery he eats with a fork instead of being fed by Nakamura. Trivia notes that because the students still wore military uniforms while wishing him a happy birthday, he never gets to blow out the candles.