Long, long ago, there existed a world of magic and science. God, afraid of man's potential, split the world in to the world of science, Elde, and the world of magic, Fandavale. One day in Fandavale, a terrible witch named Cendrillon (Cinderella) revives. Cendrillon plots to rule both worlds, and searches for the "key" which holds tremendous power. A young boy from Elde by the name of Sōta meets a mysterious girl from Fandavale, Akazukin, and her talking wolf companion, Val. Sōta learns that he is the key Cendrillon is searching for. Now it is up to Akazukin, Val, and the other Fairy Musketeers to protect Sōta from Cendrillon and her Nightmarelians who wish to obtain the power he mysteriously possesses.

High school science-whiz Makoto Mizuhara is working on his newest project in preparation for the school festival, alongside his best friend Nanami Jinnai. Nanami's brother and Makoto's lifelong rival, the unscrupulous student council president Katsuhiko Jinnai, is under scrutiny for mishandling the school festival planning and is convinced that Makoto is plotting to steal his position. One night, as Makoto and Nanami are taking a break with their teacher Masamichi Fujisawa, Jinnai sneaks into the science lab and sabotages Makoto's device, which suddenly opens a portal that flings all four of them into another world! Upon arrival, Makoto is immediately attacked by a horde of giant bug monsters. While running from them, he comes across Fujisawa and a girl named Rune Venus. After Fujisawa fights off the monsters, a group of dignitaries arrives, looking for Rune, their princess. They inform Makoto and Fujisawa that they are in a world called El-Hazard and take them back to the palace of Roshtaria, their kingdom. Though her advisors are suspicious of the newcomers, Rune decrees that they are to be treated as guests and quickly befriends Makoto. Unaware that Nanami and Jinnai are in this world as well, Makoto gets to work trying to figure out a way back to Earth. [Written by MAL Rewrite]

The Garadain Empire has exhausted the primary resources of their native planet, so they send different space expeditions to find a new world where to live. One of their main objectives is planet Earth. However, Zeku Alba, an alien scientist, decides to rebel against the imperial rule and flees towards the Earth, where he gathers a group of youngs gifted with the power of "psychogenesis", an ability that consists in creating solid matter from mental energy. The most gifted of the squadron is Isamu, a young orphan whose family was killed in the first attack of the Garadain Empire. He is able to generate the powerful robot Govarian, an armor with which he can battle the alien monsters and is able to regenerate thanks to the psychic energy of the pilot. Helped by two other robots created by his team-mates, Isamu, aboard the robot Govarian, defends the Earth in the long war against the alien invaders. (Source: Wikipedia)

For centuries, Heaven has required its young angels to live and study among humans in order to become full-fledged angels. This is no different for top-of-her-class Gabriel White Tenma, who believes it is her mission to be a great angel who will bring happiness to mankind. However, Gabriel grows addicted to video games on Earth and eventually becomes a hikikomori. Proclaiming herself a "Fallen Angel," she is apathetic to everything else—much to the annoyance of Vignette April Tsukinose, a demon whom Gabriel befriended in her angelic early days on Earth. Vignette's attempts to revert Gabriel back to her previous self are in vain, as Gabriel shoots down any attempt to change her precious lifestyle. As they spend their time on Earth, they meet two eccentric personalities: the angel Raphiel Ainsworth Shiraha, Gabriel's classmate with a penchant for sadism, and the demon Satanichia McDowell Kurumizawa, a clumsy self-proclaimed future ruler of the Underworld. Gabriel DropOut follows these four friends' comedic lives as they utterly fail to understand what it truly means to be a demon or an angel. [Written by MAL Rewrite]