It is the year 2004 AD, and pandemonium breaks as a mysterious frog-like alien race fills the sky with UFOs—or so 12-year-old Fuyuki Hinata dreams. Coincidentally, Sergeant Keroro, leader of a preliminary squad for the Keronian invasion of Pekopon—the alien name for Earth—begins his mission by invading Fuyuki's home. After subduing the boy and his sister, Keroro plans to reunite with his comrades and return to the mothership to repair his invaluable invasion device, the Kero Ball. Unfortunately, he receives word that headquarters has abandoned his unit's retrieval due to an unprecedented issue that forced the rest of the Keronians to flee. Consequently, Keroro is forced to stay at the Hinata residence together with the friendly, starry-eyed Fuyuki; his athletic, short-tempered sister Natsumi; and their hardworking, attractive mother Aki. Now stuck until further notice, Keroro and his platoon spend each day plotting world domination, but are thwarted each and every time by various unexpected factors. Nevertheless, as they live alongside humans, they learn to treat them as friends and allies, forming comedic yet meaningful connections that make their lives on Earth worthwhile.

Battles continue between Penguin Empire, the mysterious life form which arrived on earth all of a sudden, and Beauty Salon Prince, the secret anti-Penguin organization. In order to fight Penguin Empire's gigantic Penguin Robot, Beauty Salon Prince has developed their ultimate weapon, Daimidaler, and is now looking for the pilot. They choose Koichi Madanbashi, a hot-blooded high school boy who is mad about big boobs, because he is the factor of Hi-ERo particles, the source of unknown energy. (Source: Showgate)

Akito doesn't want to fight. Despite a childhood spent on the anime Gekiganger 3, a Mecha show, he'd rather cook than pilot a Mecha. Fate intervenes when his home on Mars is destroyed, and he is transported instantly to the Earth, mysteriously. He has questions no one can answer fully, but follows a girl from a chance meeting in hopes to discover any. The girl, Yurika, is captain of the private battleship Nadesico, and in order to follow her, he enlists as their cook. Possessing the nanite implants that allow to control mechas, he's a handy backup pilot for the mechas of the Nadesico. He joins a crew bent on avenging Mars that seems to be composed of only misfits, otakus, and ditzes; however, in reality, they are handpicked experts. They take their own private war back to Mars to face the harsh reality that life may not always be like a Giant Mecha series. (Source: ANN)