Turned into a toddler by a drug from Aoi. First person: I (rough). Second person: you (blunt). Third person: [Name]-tachi. Calls Shion "Shion-mama." He trains by swinging a sword around the house and tries to protect Shion even in his toddler form. Wears a red and white sukajan over a black and yellow inner shirt, beige-colored shorts, 7-fathom leggings, and a bandana over mane-like red hair. Energetic and kind, bad at studying but an athletic monster. 6th grader, but about 4 years old when regressed. Dreams of becoming the strongest hero who surpasses his mother.

Turned into a toddler by a drug from Aoi. First person: I (soft). Second person: you (polite). Third person: everyone. Calls Shion "Shion-mama." Loves studying, terrible at sports, and has a messy sleeping posture. Wears a simple white shirt with a blue tie, indigo trousers, and has neatly groomed blue hair with a slight curl. His intellect is far beyond a primary schooler, but he has zero athletic ability. 6th grader, but about 4 years old when regressed.

Turned into a toddler by a drug from Aoi. First person: Tokotan. Second person: [Name]-tan. Third person: everyone. Calls Shion "Shion-mama." Bad at schoolwork but excels at arts and crafts. Average athletic ability. Uses childish speech. Can build a robot in an instant. Wears yellow work clothes with a lab coat, has a messy brown bob, and a yellow helmet that looks like it could deflect any attack.

Became the mother of four: Hiro, Aoi, Tokotan, and Guest. Calls everyone "[Name]-kun" or "[Name]-chan." First person: Shion. Second person: [Name]-kun / [Name]-chan. Third person: [Name]-kun-tachi / [Name]-chan-tachi. Loves magma diving and sleeping in fluffy futons. Apparently wants to escape the brutal projects Aoi prepares. Kind-hearted and dotes on the four children. Has purple hair in loose twin tails, round glasses, an off-the-shoulder miko-style outfit with a miniskirt. A kind and hardworking person.

The one who gave the regression drug to Hiro, Aoi, Tokotan, and Guest. Shion's partner who prepares the projects. First person: I (soft). Second person: [Name]-kun / [Name]-chan. Third person: everyone / [Name]-kun-tachi / [Name]-chan-tachi. Aoi mostly just watches the chaos unfold.