Second TV (flash animated) series of Keroro Gunsou.

Keroro is a frog-like alien from planet Keron, who's on a mission to conquer Pekopon (Earth). However, when his cover is blown, his battalion abandons him and he ends up in the home of the Hinata family. There, he's forced to do household chores and sleep in a dark basement that was once a prison cell haunted by the ghost of an innocent girl. Keroro and his other 4 squad members continue with their plans to conquer Pekopon, aside from building Gundam Models and being lazy in various other ways...

Unsuspecting inhabitants of the planet Earth are going about their business, enjoying a bright and particularly beautiful sunny day, when a young Japanese boy spots a shiny object falling from the sky... Has an alien invasion finally begun? Elsewhere in Japan, Keroro, frog sergeant and leader of the Space Invasion Army Special Tactics Platoon of the 58th Planet in the Gamma Planetary System, has discovered the perfect hideout. He infiltrates the home of the Hinata family in an attempt to establish a headquarters that he and his troops could use to prepare for world domination... but earthlings Fuyuki and Natsumi Hinata are too much for him to handle! Natsumi instinctively calls them out of hiding, leaving the hapless sergeant no option but to reveal his secret identity. The two siblings soon welcome the sergeant to their home, all thanks to Fuyuki’s generos—err... curiosity. The Sergeant has successfully infiltrated his first target area! Or has he? Join Keroro Gunsou in his dastardly attempt to take over the world!

Keroro is a frog-like alien sent from his home planet on a mission to conquer Earth. But then his cover is blown, his battalion abandons him and he ends up in the home of the Hinata family where he becomes friends with Fuyuki and gradually starts to forget about his mission, enjoying life on earth.It is a day just like any other when Keroro skips out on simulated battle training in favor of buying the newest Gundam model with Fuyuki. On their way home, they stumble upon a hidden shrine, where they end up causing damage to a shining orb uppon exploring it. That night, Keroro finds a big X on his face, which causes him considerable distraught. The next morning, a breaking news story shows that the X has spread to more than just Keroro, giving the people of Tokyo telepathic abilities, including the Hinata Household and the Keroro Platoon. The Earthlings seem to think this is a great gift, but the mark may actually be part of a Pekopon invasion older than time itself.

During a vacation Natsumi is visited by two male and female aliens named Meru and Maru. After becoming the Deep Sea Princess, Natsumi gains feelings for Meru who is haunted by his traumatic past. Having grown accustomed to Natsumi's title, the Keroro Platoon expects a calm vacation; however, their vacation is cut short and turns into a fight for survival as an alien creature that Fuyuki has adopted reveals itself to be the enemy of the kingdom and now sends creatures of mass destruction to assassinate Natsumi, and any who stand in their way.

The movie begins with Fuyuki Hinata and the Keroro Platoon exploring an abandoned temple in the mountaintop city of Machu Picchu in Peru. While on the exploration, Keroro accidentally sets off a trap, and by chance they find a hidden chamber with a large blue crystal in the center, on a stand that has a key in it. Keroro leans on the key, causing the room to activate a mysterious machine, this caused the entire temple to shake. As soon as the group realized what was happening, they run out of the room. While running, Keroro accidentally loses his Kero Ball while Fuyuki catches a fleeting glimpse of a glowing young woman as he is running out, and tells Keroro that there was a girl in the room, but he is forced to leave the room before he can say anything else. The group successfully escapes, while the girl (now sprouting a pair of glowing wings) watches them leave - while back in the chamber, something is growing within the crystal...

Mysterious giant beings called "Ryū no Shippo" (Dragon Tails) appeared across the world. Due to the danger it could bring, the Keroro Platoon did a worldwide research on the Dragon Tails, but Tamama suddenly disappeared during the research. Because of this, the whole platoon started their search for Tamama and ended up in Mont-Saint-Michel, France where they met mysterious girl named Sion, who holds the mysterious Ryū no Hon (Dragon Book). But little they know about the secrets about her and the worldwide calamity that would destroy the entire world, as they know it...

One day, a stone carving bearing an uncanny likeness to Keroro arrives at Fuyumi's place. To solve this mystery, the Keroro Squad travels to the isolated and mysterious Easter Island. There, they meet harmless spirits known as Mana, and the odd twins Io and Rana. Lastly, there is Akuaku, a legendary evil spirit recently awoken from its long sleep.

This was the 14-minute movie that was screened in theaters with Keroro Gunsou Movie 3. It became the prequel to the Mushakero in season 5 of the main Keroro Gunsou anime series. It takes place in Ranstar where the Keroro platoon are up against the Vipers. The whole setting of Ranstar is based on the Sengoku Era of Japan, and all characters are dressed in that fashion.

The anime adapted from the manga remake version of the Korean webtoon "A Simple Thinking about Bloodtypes" involving the faceless and nameless characters of four different blood types to discuss about popular anthropomorphized blood types (the stereotypes about the blood types) in Japan and Korea.

Second season of Ketsuekigata-kun! series.

Third season of the Ketsuekigata-kun! series.