Ken Sudo cuts an imposing figure at 183 cm tall, his dyed red hair and sturdy, muscular build radiating athletic intensity. His wild, aggressive clothing style often features undone upper shirt buttons. Raised by a janitor father after his mother left, Sudo abandoned academics for sports. Though typically averse to teamwork, he discovered basketball and excelled, earning a recommendation to a prestigious high school. Violent incidents led to that application's rejection, prompting him to enroll in Advanced Nurturing High School for its financial benefits and guaranteed future. Academically, he started at the very bottom of his year, grouped with Kanji Ike and Haruki Yamauchi as the "Three Idiots of D-Class." He slept through classes, resisted studying, and possessed a volatile temper, nearly fighting C-Class students over mockery and grabbing Suzune Horikita's shirt when insulted. Basketball remained his sole priority; he aspired to turn professional and became the only first-year regular in the school club, boasting exceptional athletic ability and high physical aptitude scores. Basic academic knowledge, like the value of pi, eluded him. Key events forced change. He nearly faced expulsion for failing a midterm exam by one point, saved only when Suzune Horikita and Kiyotaka Ayanokōji secretly sacrificed 50,000 private points each. Later, Kakeru Ryūen and C-Class students framed him for a staged stairwell fight, again risking expulsion. During the hearing, Horikita defended him, exposing inconsistencies in C-Class's story with evidence from witness Airi Sakura, leading to the complaint's withdrawal. These rescues fostered deep gratitude and one-sided romantic feelings towards Horikita. His character evolved significantly. Influenced by Horikita's interventions, he committed to academics, eventually achieving his class's most improved grades. He learned to manage his anger, think before acting, and prioritize class interests. By his second year, he became a dependable core member of Class 2-D, contributing to sports events and class strategies. He defended Ayanokōji against accusations of cheating and heartlessness during class meetings, acknowledging Ayanokōji's hidden abilities while keeping promises about their extent confidential. He advocated for collective judgment over ruthless pragmatism in leadership discussions. His relationships were complex. He maintained close friendships with Ike and Yamauchi, sharing misadventures like attempting to peep on girls during a pool outing. After Yamauchi's expulsion, he grew closer to Ryōtarō Hondō. Trust developed with Ayanokōji, evolving into a genuine friendship. His interactions with Horikita shifted from hostility to admiration and unrequited love, culminating in a confession during a second-year school trip that she gently rejected. He accepted this and began spending time with Mei Onodera due to shared habits. Antagonistic ties persisted with Ryūen, whom he viewed negatively for repeated schemes, and Rokusuke Kōenji, whose arrogance he disliked despite respecting his athletic skills. In special exams and events, he demonstrated loyalty and growth. He helped Ayanokōji and Kōhei Katsuragi smuggle a gift off-campus by exploiting basketball tournament logistics, motivated by a 100,000-point reward. During the uninhabited island exam, he criticized Kōenji for abandoning the class. His journey from a volatile troublemaker to a responsible class pillar was noted by teachers as significant personal growth.