This is a love story of Aruto Hiden and Izu becoming a couple after dealing with a Human/Humagear hybrid known as Alter who has consumed Ark to destroy humanity and machines. Izu learns how to be a girlfriend for Aruto with the help of Naki and Rin while the other allies of Kamen Rider Zero-One search for Alter as Kamen Rider Giff-One who plans to steal all of the Progrise Keys from every Kamen Rider in Japan to obtain the power of the ultimate Progrise Key of the universe.
5 parts