Demon Lord 2099, Vol. 4 (light novel)

In the futuristic Fused Era, Veltol Velsvalt can become anything-a wildly popular streamer, an exchange student at a prestigious magic school, even a prisoner with a 2099-year sentence. And his next challenge is...a detective?! It's time for a whodunnit in Washington, the Endgame City, with the Demon Lord at the center!