Innocent Blood
(1992)

Marie (Anne Parillaud) and Joe (Anthony LaPaglia) kill Sal’s (Robert Loggia) transformed goons at Sal’s strip club, and then Joe kills Sal by setting him on fire and then shooting him in the head, causing him to fall to pieces.

Ashamed of who she is and what she caused, Marie sets out to commit suicide by walking into the sunlight, but Joe gets her to change her mind by professing his love to her. They check into a hotel room so Marie can get out of the sun, and Marie decides to pursue a relationship with him.

 Thanks Tornado Dragon!