Kamen Rider OOO X Love Live! Perfect Dream! Idol's Desire (male reader insert)

Years after the final battle of OOO's, Hino Eiji found a homeless boy all alone with no memory of his parents or why he's homeless, all he remembers is his name, Y/N L/N. Hino Eiji adopts the boy and he starts travelling with him. Once Y/N got to the age of a high schooler, he and Eiji departed from each other, Eiji left him with a broken red medal. Unknown to him, old enemies of Eiji get revived by a person who wants to destroy the world. Will Y/N be able to figure out the secret of their revival? Happy birthday to OOO's!