Black Mistress Contract The man I loved without knowing was from the underworld. Serious office worker Miyata Ayaka felt emptiness in her cold marriage with her husband. One night, Ayaka was saved by a mysterious man named Sakurai whom she met by chance, and her heart was shaken. But Sakurai was a dangerous figure living in the underworld. He was someone she shouldn't be drawn to, yet she couldn't resist her feelings and desire. What awaited Ayaka beyond the line she crossed was an ending she never could have imagined.