Marinette Dupain-Cheng never imagined her life would become entangled with the League of Assassins. She was used to secrets, responsibilities, and carrying the weight of being a hero - but nothing could have prepared her for a vow she never agreed to. Forced into a betrothal arranged by the League, Marinette suddenly finds herself connected to Damian Wayne, the heir to a legacy built on shadows and blood. Cold, distant, and unwilling, Damian makes it clear from the beginning that this arrangement is nothing more than duty to him. He believes his heart already belongs to someone else. And Marinette has no intention of competing for it. But living under the same vow changes things in ways neither of them expect. Between silence, tension, misunderstandings, and quiet moments neither can ignore, boundaries begin to blur. In a story where neither of them chose the promise that binds them, they'll have to decide whether fate truly controls everything - or if something else can grow from a vow not chosen.