Sergeant Keroro

Keroro is a sergeant and the leader of the Keroro Platoon. His formal introduction is The Gamma Planetary System, the 58th Planet, Space Invasion Army Special Tactics Platoon Leader, Sergeant Keroro. He is in the Keron Army, the army from his home planet.

Keroro is an adult Keronian with green and white skin, with a yellow hat and star on his belly. The star insignia on his hat is red. Keroro has no eyebrows. He looks similar to a cartoonish frog.

He has an affinity for disguises and is seen throughout the series with different wigs and costumes, meant as attempts to impersonate character archetypes for various schemes, as well as Pekoponian (Human) Suits for blending outside the house.

Keroro's blood type is O and his body fat percentage is 30%. He is 55.5 centimeters tall (1.8 ft) and weighs 5.555 kilograms.

Keroro is 10500-years-old in Keronian years. Personality-wise, Keroro as a 45 year old.

In the anime, Pururu is stated to have been born in July 1st, 1970 (Keronian calendar). Since Keroro is around her age, he would thus likely have been born around the same year.

Normally, Keroro speaks akin to an old military soldier.

Keroro usually ends his sentences with 'that is it' as a standard military sentence ending. Keroro says a repeating "gerogero" when resonating. Whenever Keroro is scheming, he emits a raspy "Ge~ro gero gero..." or "Gero Gerori".

He usually uses "frog" in the place of profanity; for example, "What the frog" or "Oh my frog" have been used frequently.

Keroro is indecisive, scheming, and complacent, but empathic and kind at heart. Likewise, he can go from cowardly and slothful to surprisingly aggressive and determined, depending on the situation. Though possessing quality leadership skills, Keroro rarely acts on them, preferring to read manga, watch television, and build Gundam models.

Since childhood, Keroro was a regular trouble-maker, as well as a bully at times (mostly towards Dororo). Furthermore, he often acted too arrogant for his own good, which frequently led to failure. However, he also proved very resilient against cruelty, much to Dororo's admiration.

In adulthood, Keroro remains mostly the same, although less "bratty" in attitude. Still, if upset, Keroro can end up crying and/or throw a tantrum. Moreover, he is reluctant to fight back whenever mistreated, especially from physical threats.

When exposed to too much humidity, Keroro reverts to a state from "Back Then". In this state, he becomes more competent and ruthless, even against Natsumi herself. The only way he can revert to his normal self is if eaten by a Nyororo or scared by Fuyuki's wrath.

While downright childish at his worst, Keroro is a good caretaker, looking after Kiruru and Babubu extremely well. Moreover, he refuses to abandon people that truly need help, to the point to protecting Kiruru from the Keron army itself.

Having a constant need to entertain the masses, Keroro compulsively slips on a banana peel whenever he sees one on the ground. Likewise, Keroro is prone to referencing pop culture at random, even playing them out as a form of comedy.

In spite of his comedic nature, Keroro is rather sharp-minded at times, bringing up good points repeatedly. More often than not, he also stops his subordinates from engaging in petty squabbles, being the only one capable of fully uniting them as a team. Overall, Keroro's demeanor fluctuates significantly, ranging from incompetent and selfish to capable and kind-hearted.