Shosuke Komi is the younger brother of Shouko Komi, first appearing at age 14 and currently aged 15-16. He attends Kisai High School, progressing from first-year to second-year student. He possesses dark purple hair and eyes, a pale complexion, and stands 173 cm tall, weighing 40.8 kg. His soft, charming facial features resemble his mother and older sister. He typically wears black or grey clothing, favoring short-sleeved t-shirts and jeans. His unkempt hairstyle echoes his maternal grandfather, Komi Shoujiro. Shosuke's personality is apathetic and selectively silent. Unlike his sister's social anxiety, he avoids verbal communication because he deems it unnecessary or bothersome, though capable of speech. Preferring solitude, he consistently ignores social invitations like lunch offers, leading others to mistakenly assume a communication disorder. Despite this aloofness, he demonstrates diverse skills including model repair, swimming, violin-making, and engraving Buddhist prayers on rice grains. Significant development occurred in his background. At age four, he was cheerful and attention-seeking. By age six, he shifted focus from making friends to helping others form friendships. A close friendship with Mizuhara Hayato ended abruptly when Hayato reacted angrily to Shosuke losing a swimming race, causing his cheerful demeanor to fade. Around age 13, he deliberately adopted a stoic personality similar to his sister's to make her feel less isolated in her communication struggles, solidifying his belief that communication was unnecessary. He lives with parents Masayoshi and Shuuko Komi, maintaining a silent but supportive dynamic with Shouko. His mother Shuuko is energetic and sociable, contrasting his reserve, while father Masayoshi shares Shouko's social anxiety, making Shosuke's elective silence distinct. He interacts with Hitomi Tadano, his sister's friend's younger sister, who forcefully includes him in activities; Shosuke shows no overt enthusiasm but tolerates her presence without resistance. His name "Shousuke" combines "laugh/smile" (笑) and "help/assist" (介), contrasting his expressionless nature. The surname "Komi" connects to the series theme, playing on "komyushō" (communication disorder). He prefers mackerel and the color black. During cultural festivals or public appearances, his striking looks and aloof demeanor attract female peers who idolize him as a "bishounen" (beautiful boy), attention he dismisses as annoying. His core traits remain consistent across media: elective silence, apathy toward socializing, and hidden competencies. His backstory with Mizuhara Hayato and deliberate emulation of his sister's behavior are pivotal to his character.