Council of Swordmasters

The Council of Swordmasters (剣聖会, Kensei-kai) is a group of the most renowned master swordsmen that convenes in times of crisis. According to Haragiri, the council was created to improve the swordsmanship of its members.

Monster Association Arc
A meeting of the council is called by Atomic Samurai to convince its members to help in defeating Garou. Atomic Samurai worries that despite Bang's strength, he might not be able to bring himself to kill his student. Thus, Atomic Samurai wants to find Garou before Bang and kill him. The council agrees to Atomic Samurai's request, for which he is grateful, but Haragiri reviles his plea and status as a hero. Haragiri reveals the monster cells the Monster Association had given him. As he tells the council about the Monster Association, he transforms into a monster. He orders the others to eat the cells and attacks Atomic Samurai. However, Atomic Samurai quickly slices him into pieces.

Trivia

 * The Council of Swordmasters is also known as the Holy Order of the Sword in the subbed version of the anime.