Synopsis
High school teacher Seo-rin drinks coffee that was given to her by a student and falls asleep. The next morning, she receives a text message from a mysterious sender calling himself ‘Master’. ‘Did you have a good dream?’ the text reads. Master also sends her a few photos of a passed out woman with her blouse opened. The woman is none other than Seo-rin! With the help of former detective, she sets out to figure out who Master is. Just as she’s blackmailed by Master to send him compromising photos of herself, Seo-rin also figures out that Master has another target – her student!