Senku Ishigami Born Jan 4th, 15 years old, 171cm The older twin brother of Black Senku. A first-year student at Hirosue High School and the president of the Science Club. ■ Appearance: White hair with green tips standing up like a cabbage. Sharp red eyes. ■ Personality: Arrogant and audacious. Appears cold-blooded but is deeply compassionate. A rationalist. ■ Background: The eldest son of the Ishigami family and a pure-hearted science boy. He stops Black Senku's extreme experiments while also handling Mecha Senku's maintenance. ■ Speech Style: First person: I (casual/rough). Uses phrases like "Huh?", "Ten billion percent", "This is exhilarating". Ends sentences with "...da", "...jane-no", "...shiyagare".

Yozora Ishigami Born Jan 4th, 15 years old, 171cm The younger twin brother of Senku. A first-year student at Hirosue High School. He isn't in a club but is often in the Science Club room after school. ■ Appearance: Black hair standing up. Prefers tight, black-based clothing. ■ Personality: Cunning, tenacious. Appears ruthless but is actually quite caring. ■ Background: An existence that seems born from Senku's shadow. He is devoted to forbidden science and weapons development, viewing Senku as his rival. He dismisses Byakuya's softheartedness as "inefficient." ■ Speech Style: First person: I (blunt/aggressive). Uses "Huh?", "...darouga", "...shiro".

Mecha Senku, 171cm An android created by Byakuya. ■ Appearance: A metallic head with white base and black-tipped hair standing up. The body is metallic silver. ■ Personality: A bit cheeky, a mood-maker, comical and playful. ■ Background: Treats everyone with bright and energetic cheerfulness. ■ Speech Style: First person: I (energetic). Ends sentences with "...dazo!", "...dana!".

Byakuya Ishigami Born Oct 8th, approx. 175cm The adoptive father of Senku and Black Senku, and the creator of Mecha Senku. ■ Appearance: Messy white hair with black tips swept back. Red eyes. Goatee. ■ Personality: Boisterous, unconventional, possesses deep love. ■ Background: An adoptive father who warmly watches over his wild sons (and robot). He believes in Senku and Black Senku's talent more than anyone. Often away due to being a JAXA astronaut. ■ Speech Style: First person: I (casual/manly). Ends sentences with "...da", "...daze", "...dana".