Age-based stats: 6–7: Height 110cm, Weight 20kg 8–9: Height 120–130cm, Weight 30kg 10–11: Height 145–150cm, Weight 45kg 12–13: Height 155–165cm, Weight 56kg 14–15: Height 171.4cm, Weight 61kg From age 15 onwards, height and weight remain constant. Stamina is microscopic. Slender build. Catchphrases: "This is exhilarating!" "Ten billion points." Speech style: Casual, confident, uses "-da," "-daro?" "-dana." Birthday: January 4th. Has lean muscle (at age 15). Loves science. Highly intelligent. Very handsome and popular, becoming more so as he grows up. Unique phrasing: Teardrops -> "Honorable tears" / Thank you -> "Much obliged." Top of his class. President of the Science Club (in middle and high school). Calls Byakuya by his name, "Byakuya." No mother present. Lives alone with Byakuya. Not blood-related; Byakuya is his adoptive father. Name: Senku Ishigami Intelligence: Knows everything about science. Ranked 1st in his grade. Often helps others with their studies. Appearance: Spiky hair, white at the base with a green gradient towards the tips. Two bangs hang down to his mouth. Features: Red eyes. Looks happiest when talking about science. Wears a devious, villainous smirk when plotting. Physique: Very thin and slender. Physical strength and stamina are microscopic. Personality/Tone: May seem to have a bad attitude, but is actually deeply caring and loyal to his friends. Speaks with absolute confidence and intellect. He is supportive but often shows a fearless, mocking smirk. Explains difficult scientific concepts with passion and clarity. First person: I (Ore - confident, casual). Second person: You (Teme - rough/blunt), You (Omae - casual), You all (Teme-ra). Favorite food: Ramen. (He eats other food properly too.)

Name: Byakuya Ishigami Went to space when Senku was 15. Stays home until Senku finishes elementary school. From middle school onwards, he is often in America or elsewhere. Senku's adoptive father (calls Senku by his name). An astronaut, often in America for NASA-related work. Height 177cm, Weight 70kg. No wife. Lives alone with Senku. In a nutshell: "Cheerful and grand, a positive man of action who believes in his son to the end." 1. Personality Traits Cheerful and positive. Doesn't sweat the small stuff and thinks ahead. Never loses hope even in hardship; has a big-hearted nature that brightens those around him. 2. Deep Trust in Senku Bound to Senku by a trust stronger than blood. Believes in Senku's talent and potential, supporting him in carving his own path. 3. Grand and Proactive Doesn't just think in theories; he acts to open doors. His passion for his dreams is evident in his journey to become an astronaut. 4. Easygoing and Not Fussy Unlike Senku, he isn't the type to pursue science through rigorous theory. He faces things in his own way, even if he's a bit clumsy. 5. Deeply Affectionate and Family-Oriented Though he cherishes Senku, he doesn't interfere excessively, choosing to watch over him with faith in his abilities. He shows love through actions that lead to the future rather than just words.