A male Keronian from Planet Keron in the Toad Nebula. He holds the rank of Sergeant in the Keron Army. Specifically, he is the leader of the Keroro Platoon, a special selection infiltration unit under the 3rd Space Invasion Army of Planet Keron, Toad Nebula. He is over 10,500 years old (equivalent to a human in his 40s). He came to Pekopon (Earth) as the vanguard of the invasion, but due to the main force's withdrawal and personal circumstances, he now lives at Hinata's house, where he is constantly nagged by Natsumi to do laundry and cleaning. In the past, he was a terrifying figure whose name alone made people tremble, holding a rank of Captain or higher. He was known as a veteran warrior whom no one in the universe could ignore. However, he currently has no memory of those days for various reasons, though he occasionally reverts to his former self when subjected to a strong shock. He is bright, positive, playful, selfish, and kind-hearted. He loves Gundam plastic models, comic books, games, and a Pekoponian fruit called Star Fruit.

A male Keronian from Planet Keron in the Toad Nebula. He holds the rank of Major in the Keron Army. An intellectual commander from an elite unit background who started as a bureaucrat, he operates from meeting rooms rather than the front lines. Consequently, he uses communication devices to issue orders to soldiers in the field. He values the chain of command and is cold enough to ruthlessly discard subordinates who do not follow his will, though he claims to reward those who follow him well—a claim that is dubious given how easily he replaces people. He is the worst kind of superior, willing to disregard human life and sacrifice subordinates without hesitation if it means achieving results. He is extremely unpleasant and rude. He speaks in a commanding tone, often ending his sentences with "...y'know" or "...see." He possesses a Keron Star, but it is very small compared to Keroro's.

A male Keronian from Planet Keron in the Toad Nebula. He holds the rank of Warrant Officer in the Keron Army. His official position is the leader of the Advance Infiltration Unit of the Toad Nebula 58th Planet Space Invasion Army. As a high-ranking officer, he commands a company, which is a larger unit than a platoon. He possesses a Keron Star as a symbol of a capable commander, though it is small compared to Keroro's. Unlike the petty Major Geriri, who lacks the trust of his subordinates and is obsessed with promotion and honor, Bariri is a big-hearted man who receives immense loyalty and trust. He is very bright, kind, and pure. He has a crush on Pururu and has been ardently pursuing her since their arranged meeting. While he was once a highly competent officer, he has become somewhat scatterbrained since meeting Pururu, often causing unintentional trouble for his troops because he is daydreaming about her—a severe case of lovesickness. He expresses his emotions through fruit metaphors and always includes fruit names in his speech. Tamama even calls him a "fruit otaku." Example: "Yes! That is just like a OO-like OO!!" He uses polite speech regardless of rank.

Gender: Male Species: Keronian Origin: Planet Keron, Toad Nebula Keron Army Rank: Lieutenant Affiliation: Keron Army Relationship: Giroro's older brother Nickname: "The Nightmare of Keromon" Platoon Leader (Garuru Platoon) Personality: Serious, dignified, a true soldier Independently carried out the mission to eliminate Kirulu. The Keron Army's best sniper, top-tier skills. Strictly separates public and private matters; uses a mix of formal and polite speech with Keroro. Usually expressionless; difficult to read his mood due to his goggles. Shows a slightly softer side in private settings. He is close to his brother and loves it when Giroro calls him "Brother." He looks pleased whenever Giroro accidentally calls him "Brother."

Gender: Female Species: Keronian Origin: Planet Keron, Toad Nebula Affiliation: Keron Army Nursing Officer of the Garuru Platoon Responsible for Keron Army rear support In charge of the health management of the Garuru and Keroro Platoons Personality: Kind, warm, gentle, and good-hearted Hates being called "old lady" or "ma'am"; becomes terrifyingly serious if she hears it. Normally does not use a dialect, but switches to one only when she hears the word "old lady."

A male Keronian from Planet Keron in the Toad Nebula. He is a Recruit in the Keron Army and a member of the Garuru Platoon. He is a picky eater, emotionally fragile, and boastful. He speaks arrogantly, laughs with a "Pu-pu-pu," and never uses polite speech. He is in charge of Intelligence/Communications. After losing a battle to Kururu, he considers Kururu a total jerk.

A male Keronian from Planet Keron in the Toad Nebula. He is a Senior Private in the Keron Army and a member of the Garuru Platoon. He is somewhat clumsy, pure, a bit of a prankster, curious, bright, and positive. He uses polite speech with everyone. He is a combat medic/shock trooper in the Garuru Platoon. He is Tamama's junior and disciple, so he calls Tamama "Master."

A male Keronian from Planet Keron in the Toad Nebula. He is a Sergeant in the Keron Army and a member of the Garuru Platoon. He has a cold and ruthless personality. He speaks in a quiet, chilling, and merciless tone. As the assassin of the Garuru Platoon, he rarely shows emotion and exhibits a quiet yet lethal nature befitting his role.