Atomic Samurai vs. Haragiri

Atomic Samurai vs. Haragiri was the fight between the S-Class hero Atomic Samurai and the monsterized swordsman Haragiri of the Monster Association.

Prologue
Atomic Samurai calls for a meeting with the Council of Swordsmen to ask them for assistance in killing Garou. Haragiri mocked Atomic Samurai's pleas, interrupting the conversation and telling everyone that the council's true purpose is to improve swordsmanship, and that meetings such as these are irrelevant and unnecessary. Haragiri prepares a speech he's been waiting to give and throws a bag to the other swordsmen. The bag is filled with Monster Cells, and Haragiri reveals that he injected himself with Monster Cells and joined the Monster Association. Haragiri then orders everyone to eat the Monster Cells, change the name of their council to the Council of Sword Demons and go beyond good and evil to reach new heights. Atomic Samurai mocks Haragiri for how far he's fallen, but Haragiri states that he already could cut beyond the speed of sound before, but now he's become much faster and he could cut all their necks with a single swing. Haragiri then tells the other swordsmen that if they refuse, they die. He also says that regardless, he was told to kill Atomic Samurai. He gives the council members 3 seconds to eat, and Atomic Samurai says no one is stupid like Haragiri.

Battle
Out of anger, his mission and an attempt to catch Kamikaze off guard, Haragiri unsheathes his sword and attempts to cut Atomic Samurai's head off. But before the monsters sword could even connect, Atomic Samurai had already taken out his sword and performed his Atomic Slash at speeds Haragiri wasn't able to react to. The monster is then cut into hundreds of little pieces, with his sword being destroyed in the process, marking the death of the fallen swordsman.

Aftermath
Haragiri is killed and Atomic Samurai decided to strike the Monster Association, along with his pupils Iaian, Bushidrill and Okamaitachi. He searches through the mountains with his disciples for any hint of the Monster Association and destroys any monsters they encounter.