Kamigoroshi no Maou, Saijaku Shuzoku ni Tensei shi Shijou Saikyou ni Naru

Synopsis

Hiram, the most powerful demon king in history, ruled over all the demon tribes. He defied the Demon God's demand for sacrifices and lost his life after fierce battle. The demon tribe will never defeat Demon God while living under its control. As long as this was the way of this world, there was no way to become the strongest. Five hundred years have passed since then. Hiram was successfully reincarnated as a "human" youth. Although he was said to be the "weakest", he was actually a human with high potential. To kill the Demon God this time, he began adventurous journey... (Source: Square Enix, translated)