Maoyu: Archenemy & Hero

Maoyu: Archenemy & Hero is also listed as Maoyuu Maou Yuusha on some trackers — same show, different title convention. ARMS is the animation studio behind this TV series across 12 episodes. It's finished airing, so the whole thing is watchable start to finish.

Genre-wise it's tagged Adventure, Fantasy, and Romance, which is the throughline if you're browsing by mood rather than by name. Looking for something similar? No Game, No Life is the nearest match on the shelf right now.