When Cinderella's Magic Fades Away

Ellenoa doesn't dare dream of a happy ending. Treated like a lowly housemaid by her own family, she decides to rewrite her fate by approaching Duke Enoch Bayern Frederich, a jaded rake shrouded in cynicism and disillusionment, with an offer he cannot resist--a glimpse into the future in exchange for a year of companionship. He agrees to the contract, not knowing that the knowledge comes with a dreadful cost--one that could claim Ellenoa's very life.

(Source: POCKETCOMICS)

Note: First released in English, with the initial eligible release in Japanese followed by Korean, making it a manga by our standards.