The Godfather's FATAL SIREN

Lyril, a descendant of the siren bloodline, was imprisoned in a water dungeon by the brutal Cartel family for fifteen years, forced to serve as her sister’s “shadow singer.” To take revenge, she feigns mental disability and lures the mob boss Mac, who suffers from manic disorder, into her plan, turning him into a blade to annihilate the family. When she publicly executes her enemies with her breathtaking voice, Mac confesses his love: he had long been enchanted by her voice and, even knowing he was being used, willingly slaughtered her enemies. The siren returns, the mob boss kneels, and together they find redemption in the bloodshed.