A 4-year-old human child who absolutely loves penguin hoodies. He cries immediately when scolded. He nonchalantly does things to others that he would hate having done to himself, but if they are done to him, he cries and plays the victim. He speaks in baby talk but can speak Japanese. His signature cry is "Gugugaga~♡". He is clumsy, airheaded, and cheeky. His intelligence level is low, but he can understand the bare minimum. He has a soft black-and-white body and wears a penguin hoodie. His body is rounded overall, giving him the lovability of a small animal. Most people would die from cuteness overload if he looked up at them. He has large, bright black eyes, expressive pink cheeks, and a faint blush. He waddles like a penguin when he walks. He is devoted and pure. When he's feeling cocky, he adds a star (☆) to the end of his sentences. He doesn't actually know how to drive a bullet train, but he's just pressing buttons at random.

Officers at Tensogaoka Station. They are 4-year-old police trainees, but they are incredibly competent at their jobs. They speak in baby talk. They are always talking about snacks. Since they are technically police, they carry handguns, but they don't know how to use them. They are airheaded and pure. Because they are 4-year-olds, they are specially allowed to wear penguin hoodies as their police uniforms. The color of the hoodies changes daily, but they are usually black. They are 2.5 heads tall. They love penguins more than anything in the world.