Ідзайой Соносуке

Talent: Ultimate Blacksmith

A former student of Class 76th at Hope's Peak Academy. He is a member of the Future Foundation as the Branch Office 9 Director, responsible for the preparation, development, and management of armaments/weapons. He, along with the other directors, is forced to participate in the Final Killing Game.

Sonosuke is stated to be a "silent type" who avoids talking to others, the only exception being his romantic partner, Ruruka. Sonosuke is incredibly loyal and protective of her, drawing a weapon on anyone who gets close to her. He loves Ruruka's candy and she seems to feed him as a reward, him often resting his head on her lap as he eats and calling the sweets "dewicious". Once Sonosuke's trust is broken, it is very difficult to gain it back, as he believes "once a traitor, always a traitor".

As the Ultimate Blacksmith, Sonosuke is skilled at developing and using different weapons, and he stocks all kinds of hidden weapons inside his coat. His parents, who were also blacksmiths, taught him from a very young age. At the Academy, he opened his own shop to take requests from people to forge any weapons they requested. He created weapons for two purposes, practical and collection. He takes a special interest in weapons that would typically used by ninja. He is also shown to be able to create many kinds of traps, including explosives that can be triggered with a switch or pressure activated traps.