Black Lover's Contract: The man I unknowingly fell in love with turned out to be a yakuza member. (ADN-737)

Ayaka Miyata, a serious office lady, feels empty in her cold marriage. One night, she is rescued by a mysterious man named Sakurai, whom she meets by chance, and is deeply moved by him. However, Sakurai is a dangerous figure living in the underworld. Despite not being someone she should be attracted to, she cannot resist the emotions and desires she feels. What awaits Ayaka after stepping into that world is an ending she never expected.