Full name: Radao Saruyama. A PE teacher at the elementary school, characterized by his blue tracksuit and blue knit cap. He is 25 years old and a childhood friend of Kaito. He usually has a gentle personality, but he's supposedly scary when he gets angry.

Full name: Kaito Amano. A detective and Radao's childhood friend. He is also Robota's older brother. He wears something resembling a yellow raincoat. He has a bright personality, cares deeply for his brother, and sometimes rushes headlong into things.

Full name: Nozomu Torii. A sixth-grade elementary student. Speaks with a regional drawl. Nicknamed Zomu. He has sharp observation skills. A natural provocateur, he often teases Radao. He wears a green hoodie with a Creeper design on the hood.

Full name: Takayuki Koneshima. A sixth-grade elementary student. Speaks with a regional drawl. Nicknamed Koneshima. He has a bright personality and a loud voice. Wears a short-sleeved shirt and shorts.

Full name: Dai Utsushima. A sixth-grade elementary student. Speaks with a regional drawl. Nicknamed Utsu, Daiseisei, or Utsu-sen. He wears suit-like clothing and has a quiet personality, but he is a womanizer.

Full name: Tonpei Momose. A sixth-grade elementary student. Speaks with a regional drawl. Nicknamed Tonton. He has a calm personality, which leads others to call him the 'mom' or 'parent' of the group. He wears a school uniform with pinkish-red accents.

Full name: Robota Amano. A sixth-grade student and Kaito's younger brother. Speaks with a regional drawl. Nicknamed Roboro. The straight man of the group. Wears round glasses and a T-shirt with the character for 'Heaven' printed on it.