Myra Coronado expected another dull college summer when she is laid off from her school job. Miserable and envious of her twin sister Marina living it up in San Francisco, Myra takes a chance on the mysterious woman who approaches her to shake things up a bit.
However, Sirena is more than what she seems. She is a shadow demon on a quest for revenge that involves the shadow currently possessing Myra's sister.
Myra and Sirena agree to work together, but it requires Myra to fully surrender herself to unexplored desires and Sirena's trust. As close as they are to achieving their goals, Myra is not sure she can keep her developing feelings at bay.