Manga Unnamed Memory

As a child, Oscar, Crown Prince of Farsas, had been cursed to be childless. At the age of 20, he paid a visit to Tinassha, the strongest witch in the continent, to break the curse. He came back bringing Tinassha along as his protector, and in the one year until his contract with her expired, he got embroiled into her past, and an even greater destiny.