Chapter 180

Working from the slime recipe recorded in their advice books, Okuda and Takebayashi engineer an artificial blood that any patient can receive during a transfusion. College coaches and pro clubs court Sugino for his pitching, while Terasaka lands a post under a politician and Muramatsu, Yoshida, and Itona each take up work in their family trades. Ritsu now lives and refines herself across the internet, ready to lend her old classmates a hand. Hazama becomes a librarian, Nakamura studies overseas, and Karma clears a civil service exam to join the Ministry of Economy, Trade and Industry.

Splashing water at one another in play, the class lets Kayano reflect on how their teacher's lessons endure in each of them and how he tied them all together. When Hara asks about her and Nagisa, Kayano says nothing has happened between them, since he keeps his focus fixed on his target.

Nagisa has drawn a rougher lot, teaching a room of delinquents where the pecking order flips everything he knew in 3-E. He notes that seven years added just a single centimeter to his height while everyone else shot up, Karma reaching one hundred eighty-five centimeters. When the ringleader rises and threatens to kill him, the very word triggers Nagisa's stun clap, and he lays a finger to the student's neck as the class gasps in awe. Picking up his attendance book with an image of Korosensei looming behind him, Nagisa sets it on the front desk and calls the lesson to order.

This twenty-three page chapter caps the twenty-first volume, Time to Say Thank You. The Japanese title Koroshi no jikan means Killing Time. It follows Time After Time and gives way to the bonus chapter Home Time.