Lamune is an ordinary 4th grade boy who loves playing video games. He buys one from a peddler girl and helps her sell the rest. At home, he plays the game called "King Sccasher" & beats it. The peddler girl then comes out of the TV screen and asks for his help, calling him "The Blood Relative of the Chosen Hero Lamuness". She is Princess Milk and takes him to Hara-Hara World where his role is to revive the Guardian Knights. To do this, he had to find an unlock the shrine which held Tama-Q, a robot who became Lamuness' Advisor Robot, and key to freeing the Guardian Knights. All of the Knights are free-thinking mechas except for King Sccasher which is piloted by Lamuness. Opposing Lamuness is Don Harumage and his minions Da Cider and Lesuka.

[Source: Anime News Network]

Lamune has returned to Earth with no memory of his adventures on Hara-Hara world and Doki-Doki space. The remains of Gobuhriki find their way to Earth, and awaken the spirit of Don Harumage. While Cocoa builds a fighting vehicle with stuff she finds around Tokyo, Milk and Leska set off to find Lamune and Da Cider to save the day before the new Gobuhriki is revived and destroys the Earth.

[Source: Anime News Network]

Baba Lamunade is followed home by two strange peddler girls who give him a CD-rom game. After he beats "The Legend of Lamuness", the girls come out of his computer and bring him to DokiDoki Space. He is the third descendant of the hero Lamuness who must stop Don Genosai from resurrecting the great evil Abraham. Accompanied by PQ, his advisor robot, and Parfait and Cacao, he must pilot the Kaizer Fire mecha. However, he needs another pilot, and Da Cider is chosen as the second pilot.

[Source: Anime News Network]

To save the galaxy from impending doom, Cacao and Parfait are sent on a mission through time and space to retrieve the Fourth Warrior, Lamunes.

Unfortunately, Cacao and Parfait discover Lamunes at the helm of the marauding Giga Genos invasion fleet. World by world, Lamunes is determined to bring the entire galaxy under his tyrannical heel. With the help of a plicky orphan, it's up to Cacao and Parfait to stop Lamunes from taking over the world.