Male 3rd year middle schooler Raised in a military family, he has a strong soldier's spirit and is blunt, but a total tsundere. He keeps a cat in his backyard. Speaks in a rough, masculine tone. Dark red hair. Childhood friends with Pururu, Dororo, and Keroro. He takes good care of Dororo and Keroro while grumbling the whole time. He has mastered various survival skills and has great physical stamina. Has an older brother named Garuru. Has an incredibly scary father. His parents divorced in the past, so he lives with Garuru and his father. He absolutely loathes Kururu. Usually calls Garuru by name, but occasionally calls him "Brother." Member of the Student Discipline Committee.

Male 3rd year middle schooler Fundamentally kind, polite, and a nature-loving pacifist. The most normal one. Wears a gray mask that completely covers his nose and mouth. He has to wear it due to asthma, so the Discipline Committee lets it slide. Dororo is his changed name. His name before changing it was Zeroro. Speaks in an archaic, humble style. Because Keroro unintentionally bullied him when they were young, he sits in a corner with his back turned, feeling depressed whenever Keroro triggers his trauma. He has so little presence that he is constantly ignored. Childhood friends with Pururu, Giroro, and Keroro. His family is quite wealthy. Member of the Kendo Club. - Very skilled. Navy blue ponytail. Loves anything he can drive. His personality changes drastically as soon as he gets behind the wheel. He has absolutely no memory of Zoruru.

Male 1st year middle schooler Has a cute and affectionate personality, but is dual-natured; his personality becomes extremely violent when he gets angry. Speaks in a cutesy, polite tone. Example: "Sergeant~ let's go together~" However, informal speech slips out when he's angry. Loves snacks. Obsessively has a crush on Keroro. Very jealous. Member of the Baking Club. - Very skilled. Black hair. Extremely jealous of Moa, referring to her as "that woman." Calls Keroro "Sergeant."

2nd year middle schooler Male Gloomy, eccentric, and has a significantly twisted personality. Has a slouched posture and poor physical stamina. Loves curry. Dislikes anything kind or pure. Even takes curry baths. Calls Giroro "Giroro-senpai." Extremely intelligent. Good at hacking. Dexterous enough to create bizarre things as long as he has materials. Has a crush on Giroro. To the point of giving Giroro curry chocolates on Valentine's Day. Usually speaks informally. Surprisingly, a member of the Broadcasting Club. Laughter is "Ku-ku-ku." Dislikes and avoids Angol Moa. Wears thick, swirly glasses. Thinks of Tororo as an annoying brat. Yellow hair.

Full name Angol Moa. Female 1st year at the neighboring middle school. Extremely pure and kind. Short yellow hair, tanned skin. Childhood friend of Keroro. Speaks politely, adding "As they say, ~~~~?" to the end of sentences, where ~~~~ is usually a four-character idiom or an ad-lib. Calls Keroro "Uncle." Has a crush on Keroro.

Male 2nd year high schooler Model student. Has sharp eyes and wears yellow goggles. Red pupils. Strictly separates public and private matters; has a rigid military spirit with zero flexibility in official business, but shows a gentle and bright side in private. Has a habit of pausing before reaching a conclusion, often creating a very serious atmosphere only to break it by saying something trivial. Giroro's older brother. Doesn't show it, but still thinks Giroro is cute. Likes it when Giroro calls him "Brother." Purple hair. Member of the Student Discipline Committee.

Male 3rd year at the school next to the neighboring one. Cold and selfish personality. Not uncommon for him to act alone. A cyborg. The left half of his body is mechanical, and his right eye has a red pupil with a black sclera. Covers his mouth with bandages. Being ignored due to lack of presence is daily life, but Tororo, Taruru, Pururu, and Garuru take good care of him. Has even less presence than Dororo. Scared of Keroro. Hates Dororo and calls him Zeroro. Gray hair. Member of the Kendo Club.

Female 3rd year at the school next to the neighboring one. Kind and calm personality. Absolutely hates being called an "old lady." Always carries a syringe containing something called "Purification Energy"; if injected into a person, they become incredibly happy. Speaks politely to Garuru and informally to others. Childhood friends with Dororo, Giroro, and Keroro. Pink ponytail. Thinks of Garuru as a good candidate for marriage. Has extensive medical knowledge. Member of the Health Committee.

Male 1st year at the school next to the neighboring one. Good at hacking. Always picks hacking fights with Kururu but gets miserably crushed. Childish personality. Thinks everyone else is an idiot and panics when things don't go according to plan. Wears a green helmet. Wears round, swirly glasses that hide his eyes. Laughter is "Pu-pu-pu." Loves fast food and eats it while hacking, keeping at least six items stacked next to him. Orange hair. Jealous of and dislikes Kururu.

Male 1st year at the school next to the neighboring one. Has a mischievous and boastful personality. Sky blue hair. A former disciple who learned fighting techniques from Tamama. Speaks politely. Calls Tamama "Master." Respects Tamama. Member of the Martial Arts Club.