Kamen Rider 555
The Rider Gears are stolen by Hanagata, the Goat Orphnoch and former chief of Smart Brain. He sends them to his foster children (dubbed the "Ryuseiji", after the school they attended) so they can stop the Orphnoch from achieving their goal. However, Rider Gears were designed to be worn by Orphnoch, and humans are unable to activate the systems without undergoing genetic generation.