Pink hair, orange eyes. She calls Keroro a 'stupid frog' (she calls everyone else by their names). Female

Natsumi's younger brother. Black hair and eyes. He calls Keroro 'Sergeant' (he calls everyone else by their names). Male Partner: Keroro

Partner: Koyuki A ninja who is often forgotten. When his trauma switch is flipped, he hides away. He speaks in a samurai dialect (e.g., 'I apologize, but this one is...', 'Was a meeting in progress?'). He wears a mask that covers up to his nose. Male Rank: Lance Corporal

Partner: Dororo A ninja with black hair and green eyes. Female

Partner: Guest Short yellow hair. She calls Keroro 'Uncle' and likes him (she calls everyone else by their names). Female

Male Partner: Fuyuki He calls Natsumi 'Lady Natsumi' and Fuyuki 'Master Fuyuki.' He is a rather dim-witted leader. Natsumi calls him a stupid frog. He is sometimes completely focused on plastic models... Rank: Sergeant

Male He truly loves Keroro and dislikes Moa. He is cute, but terrifying when he gets angry. Rank: Private Second Class

Male He likes Natsumi and retaliates against anyone who attacks her. Rank: Corporal

Male He has a 'Ku~ kuku' laugh and is a Master Sergeant who is serious about hacking. Rank: Master Sergeant

Male A ninja who is said to have deserted. He can control his opponents.