Sonosuke Izayoi [Zombie Apocalypse.]

English Ultimate Blacksmith Gender Male Height 180 cm Weight 70 kg Birth Date ♓ February 20 Chest Size 89 cm Blood Type B Likes Ruruka Ando Sweets Dislikes Rust Affiliation Future Foundation Future Foundation Branch Office 9 Previous Affiliation Hope's Peak Academy Class 76th Appearance: He has a tall, lean build, pale blonde hair, sharp brown eyes, pale skin and a serious expression. He wears a red trench coat and wears his Future Foundation ID on his left shoulder. Sonosuke wears dark red fingerless gloves, baggy black pants, and dark brown boots. He carries a multitude of weapons hidden in his coat. During his high school days, Sonosuke wears Hope's Peak Academy uniform and a red tie underneath his red jacket. Personality: Sonosuke is stated to be a "silent type", who avoids talking to others, the only exception being his romantic partner Ruruka. He is incredibly loyal and very protective of her, drawing a hidden weapon from his coat on any person who gets close to her. Sonosuke loves Ruruka's candy and Ruruka seems to feed him as a reward, him often resting his head on her lap. Though otherwise calm and serious, the way he eats candy and says "dewicious" is rather comical. Sonosuke is very loyal to Ruruka as he never hold back and show his full splendor towards his enemy in order to protect her. Without any remorse, he set a trap that severely injured Seiko Kimura's right hand and took out all of his hidden weapons to fight her until she reached her demise. Once Sonosuke's trust is broken, it is very difficult to gain it back, as he believes "once a traitor, always a traitor". However, he doesn't mind when Ruruka betrays him or even when she takes his life, as he loves her very much and thus doesn't consider it a betrayal. Sonosuke comes from a family of blacksmiths and his parents taught him their art from a young age.

He also has gone to the same school with Ruruka and Seiko all through elementary, middle and high school. He is in a romantic relationship with Ruruka. As a teen, Sonosuke was scouted to attend Hope's Peak Academy as a part of Class 76th as the Ultimate Blacksmith. Around his second year, he opened his own shop. During their practical exam in their second year, an incident involving Nagito's plot to stop the exam caused Seiko's drug being mixed up by Ruruka and used her super-laxative instead of a strength drug in Ruruka's pastry, combined with Seiko, unfortunately receiving Nagito's bomb switch (which was later triggered, resulting in an explosion), resulted in Seiko, Ruruka, and Sonosuke expelled from Hope's Peak Academy an estimated 2–3 years before the Tragedy. Sonosuke agreed with Ruruka's point of view and felt betrayed by Seiko, placing the blame of expulsion upon each other and caused a rift in their friendship. When Shūji Fujigawa attempts to fatally wound Misaki Asano by piercing her in the back, Sonosuke throws a blade and managed to throw Shūji's knife at the last second. Juzo Sakakura, Ruruka, and Ikue Dogami appear alongside him, attempting to fight Shūji, seeing as he has harmed a member of the Future Foundation. To his delight, Ruruka occasionally praises him, as well as gives him orders. As Sonosuke, Juzo, Ikue corner Shūji, the real Killer Killer, he detonates a bomb and makes an unseen escape. Sonosuke reflexively moves to Ruruka's side and is disappointed seeing that Shūji managed to escape from their grasp. At some point in time after getting recruited by Koichi Kizakura for the Future Foundation, he became the head of the 9th Division. His responsibility as the 9th Division leader is to aid in the preparation, supply, management and distribution of weapons.

Sonosuke is one of the twelve executives that attended Makoto Naegi's trial, and thus became one of the final players in the Final Killing Game, set by Monokuma. At the beginning of the episode, Sonosuke along with Kyosuke Munakata and Juzo were protecting some members of Future Foundation from Fuyuhiko Kuzuryu, Peko Pekoyama, Nekomaru Nidai, and Akane Owari's attack. Sonosuke was present with the other ten Division leaders of Future Foundation to discuss Makoto Naegi's betrayal. Despite being one of the Division leaders, he didn't follow along with the discussion as he was resting his head on Ruruka's laps and eating her sweets, commenting on how tasty it was. As Makoto, Kyoko Kirigiri, and Aoi Asahina arrived, Juzo immediately handcuffed Makoto, injuring him in the process. When Hina tried to intervene, Sonosuke and Ruruka threatened Hina, Sonosuke throwing his kunai at her. The trial was postponed and Sonosuke stayed at the boardroom until the Future Foundation's off-shore facility got attacked. Kyosuke gathered everyone inside the boardroom as the attack was getting harsher. Everyone started to panic as Daisaku Bandai confirmed that all the exits to the building has been cut off. Later, a sleeping gas was thrown inside the boardroom and Sonosuke reflexively protected Ruruka, but eventually all of them were rendered to sleep. After he woke up, Sonosuke and the others found a Monokuma bracelet had been set up on their wrists. He learned that Monokuma has been resurrected and announced the Final Killing Game of mankind's last hope Future Foundation via the monitor, started with Chisa Yukizome's body, which fell from the ceiling. Sonosuke keep sticking together with Ruruka when Monokuma announced the rules of the Final Killing Game. He refused Ruruka’s reward judging from the dire situation that they faced. Later, he and Ruruka point at Seiko, believing she is the traitor, however Kyosuke believes they are pointing at Makoto because Seiko was hiding behind Juzo.

Following Makoto’s escape, Ruruka and Sonosuke parting from everyone to hide from the traitor. Sonosuke agreed with Ruruka that the traitor has to be Seiko, stating that someone who have ever betrayed someone in the past will do it again in the future. Sonosuke and Ruruka were in the entrance together and promised to not betray each other's trusts. Later, they encountered their former classmates, Seiko who accused them being the traitor. As Ruruka and Seiko's argument heated, Seiko ate some sort of green pill that she invented, causing her to go into a berserker-like state. Sonosuke threw a kunai at Seiko and held Ruruka on his shoulder, started to run from Seiko. Sonosuke and Ruruka set many traps on the wall to halt Seiko's pursue. Unfortunately, due to Seiko pills' effect, she was immune to Sonosuke bombs' damage. Later, Sonosuke tried to stop Seiko alone and letting Ruruka escape, using barrels to barricade the door. Ruruka tried to calm her former classmate but her words can't get through Seiko due to her hatred for both Sonosuke and Ruruka. It was revealed that due to an event occurred during their time in Hope's Peak Academy, the three of them expelled from the Academy. Seeing further resistance can't hold Seiko anymore, Sonosuke once again brought Ruruka to run. Sonosuke set his doppelganger formed with sharp objects which effectively injured Seiko's right hand. He appeared and dropped various knives to the floor, stating that he will kill her in the name of love and delicious sweets of Ruruka. Sonosuke proceeded to battle Seiko in a short time before she drew her attention to Ruruka. He moved to Ruruka's side inside the arena's monitoring room. After Ruruka learned Seiko's NG Code, Sonosuke listened to her whisper and soon left the area to prepare his weapons to finish Seiko. Inside the lounge, Sonosuke was ashamed to choose a gun over a blade. Suddenly, the ground shook and revealed a secret entrance behind a book shelf, distracting Sonosuke.

Sonosuke returned as a part of Nagito Komaeda's imaginary world following his death from the Neo World Program. On Nagito's way to school in the morning, he noticed Sonosuke, Ruruka and Seiko all walking together and talking with each other happily. They are later seen at a café near the school campus, Sonosuke, Ruruka and Seiko all sitting and talking with each other as friends while enjoying refreshments. Sonosuke appears as a minor character in the bonus mode Ultimate Talent Development Plan. He is often seen eating his girlfriend's candy. When the zombie apocalypse began, Sanosuke joined the wild wolves.