Emily thought she only gained a stepsister. Little did she know what she got was a predator cloaked in the most alluring disguise. Mia's first touch came beneath the water, where no one could see, awakening Emily to the thrill of forbidden desire. Their interactions grew bolder afterward, and Emily sank deeper into the entanglement. Now Emily is torn between two choices: the ordinary "normal" life she clings to desperately, and the woman who haunts every waking moment of hers—the stepsister who calls her "sister" yet makes no promises. One path is mundane and monotonous. The other fills her with fear, yet makes her heart race.