Keroro Gunsō

, released in English as Sgt. Frog, is a manga series by Mine Yoshizaki. It was later serialized into a TV anime series directed by Junichi Sato. Both the anime and manga are comedies that follow the attempts of a platoon of frog-like alien invaders to conquer Earth. Sergeant Keroro, the titular character, is the leader of the platoon, but is at the mercy of a human family of three after he is captured while trying to hide in one of the family member's bedrooms. In both the manga and anime, Keroro is forced to do meaningless chores and errands for the family after his army abandons his platoon on Earth.

The series takes its comedy from a combination of wordplay (particularly puns and homophones), physical humor, situational irony, and numerous pop culture references (especially to Gundam, Space Battleship Yamato, Dragon Ball Z, and Neon Genesis Evangelion). Various anime, games, manga, and other aspects of pop culture are parodied/referenced throughout the series as a bonus to older viewers. Both the manga and the anime are laden with pop-culture references, and even in the same story the references often vary wildly. The anime does not explicitly refer to Evangelion or other animations to which Bandai does not hold the copyrights, but only recreates the "feel" of famous scenes from these anime. The anime is much more detailed and direct in its Gundam references, however, since Bandai does hold rights to the Gundam franchise.

Plot
Both the manga and the anime focus on the steadily deteriorating conditions of the Keroro Platoon, a group of two-foot-tall frog-like invaders from the planet Keron of the gamma storm cloud system, who continuously try to conquer the world, but fail miserably each time. The platoon's leader, Sergeant Keroro, is easily distracted, and would rather spend his time making plastic Gundam models and surfing the Internet than destroying Earth, much to the chagrin of the bellicose corporal, Giroro. Aside from Keroro's laziness, the largest obstacle in the way of their mission is the Hinata Family, a trio of humans in whose care Keroro finds himself after the Keron army deserts him on earth. Keroro is kept busy with manual labour and constant abuse, primarily from the family daughter Natsumi Hinata. Aside from Keroro, there are four other members in the Keroro platoon. Each one of these find themselves in the care of a human, who are all tied to the Hinatas in some way throughout the events in the Anime and Manga.