Kunshu-sama ni Muneyake

As Captain of the Royal Guard, Aria is sworn to protect Crown Prince Julius — a guy who's brilliant at basically everything and completely aware of it. So when he casually announces that she's going to be his bride, Aria is less than thrilled. She confronts him, and Julius, being the smug royal he is, offers her a deal: beat him in any competition within six months, and the engagement is off. The catch? Nobody has ever beaten Julius at anything. This 25-episode ONA based on a WEBTOON manga sets up a fun rivalry-turned-romance in a fantasy kingdom where the tension between Aria's stubborn pride and Julius's infuriating confidence drives everything forward. Each episode runs about three minutes, so the pacing is tight and you can genuinely watch the whole thing in one sitting without rearranging your schedule. The vibe is light romantic comedy with just enough fantasy court intrigue to keep things interesting — think the dignified heroine energy of Akagami no Shirayuki-hime mixed with the playful power dynamics of Sensei Kunshu. The animation leans into that webtoon aesthetic, which gives it a distinct look compared to traditional anime. If you liked the slow-burn tension between competent leads in Snow White with the Red Hair, or you're just in the mood for a quick romance where both characters are sharp enough to keep each other on their toes, this one fits the bill nicely.