Ookami Shoujo to Kuro Ouji

Shinohara Erika, a vain 16-year-old girl, tells her friends about her romantic exploits, though she actually has no boyfriend. She shows them a candid photo of an anonymous guy as her boyfriend, yet it turns out the guy is a schoolmate named Sata Kyouya. She has no choice but to convince him to act as her fake boyfriend. Unfortunately, Kyouya may look like a sweet person, but he is actually an ultra-black-hearted sadist.