A promise made in childhood... A sister thought stillborn... And a best friend who never forgot. Yatin Taneja promised Reyansh Oberoi he'd protect his little sister. They laughed then, imagining one day she might be his bride. They thought the promise died the day she was lost... until Manya Grover arrived: fearless, chaotic, and the only woman who could stir the Leviathan inside him. Reyansh Oberoi finally finds the sister he mourned, cherished in secret, hidden from a world that would break her. Manya calls Reyansh her soul brother, teases Yatin endlessly, and tests every limit of the man who vowed to protect her. A dangerous game of love, trust, and secrets begins. Can Yatin keep his promise... and his heart?