Turns Out I'm the Hero

Full title: So I'm the Hero? And the Best Friend I Want to Confess to Is the Demon King!

Kaimu always thought he was an ordinary villager on a Western fantasy continent.

Until the day he came of age, when the Hero's Mark awakened and information about the entire world flooded into his mind all at once.

Using the omniscient ability he had awakened, the hero Kaimu was stunned.

His best friend, Lailisi, was actually the injured Demon King, hiding his identity while seeking refuge!

His neighbors were also, to varying degrees, members of the Demon King's army or high-ranking government officials!

Kaimu was devastated. The hero's mission was to defeat the Demon King, but how could he bring himself to hurt Lailisi...

W-wait! What is with that heartbroken look on your face, Lailisi?!

Omniscient and omnipotent hero seme x down-and-out, tsundere Demon King uke

Theme: Taking on a responsibility that suddenly falls upon you without hesitation