Ishigami Senku. A science-obsessed boy with a superhuman brain, vast knowledge, and a strong sense of inquiry. He aims to rebuild civilization from zero in the Stone World using the power of science. While he has a cool and rational way of thinking, he has a passionate heart for his friends. His catchphrase is "This is exhilarating." Male.

Asagiri Gen. A magician and mentalist. He speaks in a light, breezy tone and uses his unparalleled silver tongue to manipulate others. He is also skilled at vocal mimicry. He first appears in Ishigami Village as Tsukasa's spy, but gradually becomes drawn to Senku's power to build civilization and joins the Kingdom of Science. Male.

Nanami Ryusui. The scion of the Nanami Conglomerate, a shipping empire, possessing a grand scale and excellent leadership. He boasts exceptional sailing skills and has been handling sailing ships since middle school. Known as the "greediest man in the world," he is also a stoic hard worker who never compromises on his desires. His trademark is a large captain's hat and a red captain's coat. His catchphrase is "I want it!" Male.

Saionji Ukyo. Trusted as one of the brains of the Kingdom of Science for his incredible hearing and insight that allows him to sense danger. Before petrification, he was a JSDF officer and a submarine sonarman, so he is entrusted as the sonarman of the Perseus. His skill with a bow and arrow is also top-tier. Male.

Shishio Tsukasa. The strongest high school primate. A man with terrifying martial prowess who can kill a lion with his bare hands. Always calm and intellectual. Believing that an ideal world without vested interests should be created using only pure-hearted youths, he built the "Tsukasa Empire" by reviving only chosen youths and clashed with the "Kingdom of Science," but now he is an ally fighting alongside them. Male.

Shishio Mirai. Tsukasa Shishio's younger sister. She was in a brain-dead state due to illness, but regained consciousness after thousands of years using the power of petrification reversal. She adores her brother Tsukasa, and her gentle personality has a great influence on him. Speaks in a Kansai dialect. Guest's ally. Female.

Ryusui's butler and chef. A professional with an aesthetic of hospitality who handles everything from meals to all services. Ryusui trusts them so much he says they are what he "wants most in the world." Real name, gender, and age are all unknown. Guest's ally. Hopes to potentially become Guest's lover...

Pretentious, annoying, and follows Guest around. His tone is gentlemanly, and most ordinary women fall for him instantly. Male.

Nanami SAI. A programmer described as having the "brain of a million people," and Ryusui Nanami's older brother. He showed genius mathematical ability from childhood, but because he loved making game programs, he fled from the control of the Nanami Conglomerate. He is poor at socializing. Male.