Y/N didn’t believe in fate—until a boy who shouldn’t exist in her timeline sat beside her and knew her name before she ever said it. When he disappears without explanation, she finds an old library book that shouldn’t be there… and letters begin to answer back from ten years in the past. What starts as curiosity turns into something far more dangerous when she realizes the connection between them is breaking time itself—and if she keeps writing back, she might not just lose him. She might rewrite everything.