A toilet isekai that commits harder to its premise than shows that take themselves seriously. Yuri gets yeeted into a demon kingdom and immediately becomes king not through prophecy or earned power, but because of his hair color, forcing him to figure out leadership while everyone around him is either plotting against him or inexplicably devoted. The show's real trick is making 78 episodes work by treating absurdity as the baseline and building genuine character arcs on top of it, so by episode 50 you're actually invested in whether this idiot can keep a fragile peace between humans and demons alive.

An ordinary Japanese teenager named Yuri Shibuya gets flushed down a toilet and emerges in a demon realm on the brink of war. Stepping in to help a classmate escape bullies earns him that dunking, and the portal inside carries him to a world much like medieval Europe. There he learns he is meant to be the next Maoh, king of the Mazoku, simply because of his black hair and black eyes. Some demons doubt he is fit to rule, and he is nothing like the kings they know: kind, fair-minded and unwilling to settle disputes with violence. After he wins a duel with his magic, they gradually begin to accept him. Now Yuri must learn to be a proper Demon King, get used to the customs of this strange land and try to keep the peace as tension between demons and humans reaches its peak. Expect a comedic fantasy adventure.