After losing both parents overnight, Seraphina is left with Sebastian, the son of her father's mistress and the last person she should hold on to. Terrified of being abandoned again, she forces him into her home and under her control, determined to turn him into the one person who will stay by her side forever. But Sebastian refuses to accept her as his sister. He fights her, defies her, and never gives in to her threats or control. Yet beneath Seraphina's cruelty, Sebastian begins to see her loneliness, tenderness, and pain. Before he realizes it, hatred turns into something he can no longer control. As they grow closer, one question still stands between them: are they truly related by blood?