Nekokaburi Reijou Aria no Koubou

Aria, a beautiful young lady known as the "Lily of the Valley," may seem pure and modest, but she is also a jewel thief causing a ruckus in the royal capital. Raoul, known as the "Blue Moon Paladin" for his ruthless enforcement of the law, manages to discover the thief's true identity—? The battle begins between the lady thief who will never be caught, and the strict knight who never lets his prey escape!

(Source: Kadokawa, translated)