Chojuro Kon/Synopsis

History
Due to his powerful Quirk and terrifying appearance, Chojuro was ostracized and subject to discrimination, which led him to resent and hate society.

One day, Nine saved Chojuro from authorities and asked him to join his group, explaining that he will create a world where those with the strongest Quirks would rule over the weak and powerless, that way no one would be called "Villains" or monsters.

However, Nine's illness prevented their plan from going into motion, so he agreed to join the League of Villains to undergo an experiment that can grant him more power and cure his illness. Chojuro and his teammates reluctantly let Nine join the League.

My Hero Academia: Heroes: Rising
Sometime after joining the League, Nine escapes and reunites with his comrades, informing that while the experiment granted him more power, the symptoms of his illness worsened. Chojuro was vocally disappointed with the news, but Nine suggested that they look for a Quirk capable of healing his illness, then their dream would become reality.

Over the next few weeks, Nine and his crew attack various Heroes and steal their Quirks.

One night in Kyushu, Chojuro ambushes a civilian, Mr. Shimano, who has a Cell Activation Quirk that could heal Nine. Nine steals his Quirk, then destroys parts of the city using his Weather Manipulation Quirk. Chojuro, Slice, and Mummy are excited to finally set their dream and plan into motion, but their celebration falls short as Nine freezes up in pain. Nine realizes that Mr. Shimano’s Cell Activation isn't compatible with his blood type.

Chojuro and his crewmates are disappointed that their struggles to cure Nine's illness was worthless, but Slice shows a video recording of Mr. Shimano's children, Mahoro and Katsuma. Nine suspects that one of the kids must have a Cell Activation Quirk that is compatible with him, and the crew decide to look for them.

The crew hijack a ferry and travel to Nabu Island, and crash it into the harbor upon arriving. Nine orders his crew to isolate the island as much as possible by causing destruction, while diverting attention from their true goal while he hunts for the Shimano siblings. Chojuro destroys the communication towers, severing connections from Nabu Island to the outside world.

Chojuro is confronted by Mashirao Ojiro, Mezo Shoji and Fumikage Tokoyami on the beach, and begins taunting that they are too young to be Heroes. Chojuro and his Quirk, Chimera, prove to be too powerful for the students of U.A., and is able to block Mashirao's Tornado Tail Dance and Dark Shadow.

Chojuro defeats Mashirao and strangles Shoji, insulting his appearance while at it, until Tenya Iida and his team intercept the Villain. Despite outnumbering him, Chojuro proves to be unmatched by everyone.

While fighting, Chojuro notices a flare, prompting him to retreat. After arriving at a lighthouse, where Slice is taking care of Nine, they come to the conclusion that Mummy has been captured.

The next morning, a recovered Nine, Chojuro, and Slice make their way to Mount Shiroyama, when Yuga Aoyama uses his Super Move, Can't Stop Twinkling: Supernova. Chojuro breaks away from his comrades, and is further separated by shots from cannons created by Momo Yaoyorozu, causing him to plunge into a nearby waterfall.

At the waterfall, Tsuyu Asui drags Chojuro into the water before Shoto Todoroki freezes it, but Chojuro escapes the ice. Eijiro Kirishima and Tenya engage in close combat with the Villain while Shoto fights using his Half-Cold Half-Hot Quirk. Chojuro continues fighting until his body feels funny, to which Shoto reveals that Tsuyu's toxic mucus was used against him.

To nullify the toxins, Chojuro uses his Quirk to grow bigger, and fires a massive blast of fire at the students. Shoto tries blocking the blast with ice, but to no avail, prompting the four students to form a plan.

Tenya distracts Chojuro using Recipro Turbo, while Eijiro and Shoto sneak from behind. Chojuro notices, and blasts fire at the two, while Eijiro activates his move, Red Riot Unbreakable, to protect Shoto. As Eijiro loses consciousness, Shoto jumps onto Chojuro's mouth, while Tsuyu restrains his arms and Tenya holds his tail to the ground. Chojuro defeats Tsuyu and Tenya and knocks them out before Shoto defeats him by activating his Quirk to reach sub-zero temperatures, before passing out from the cold.

After Nine's defeat, Chojuro, Slice, and Mummy are arrested and taken into custody.