A Divine Crown (Highschool DXD x OC/Male Reader Insert)
17 parts Ongoing Kazuhiko Adam, or simply Kaz by his friends, was a mostly normal boy raised in Japan, he was always catching stares because of his rainbow-like eyes, but not in a good way, he had only ever made friends with other outcasts of the neighborhood.
He and his friends went on to create the "Public Service Club" in the first year of high school, performing duties for many a neighbor, whether it be simply talking with them, helping them shop, babysitting, and more.
Kaz's life gets changed in their second year after a simple call turns into something much worse, with a sickening decision none of them can ever return from.
Kaz will have to adjust to the new life he awakens to, following the orders of a girl from school, will he be able to adjust, even after learning of the true nature behind his eyes?
A Highschool DXD story with an MC that has to work up to his Overpowered self, and actually has to compete in the world of Devils and the Supernatural, has crossover characters from various other series.
And yes, he will have a harem, it's a DxD story what else would you expect?