Cinderella at 2AM Season 1 Episode 4

An unknown number keeps texting Yoon-seo's phone with messages only an ex-boyfriend would text, making her suspect Ju-won. When she confronts him about it, she makes a fool of herself. Meanwhile, the company's new venture in the vacation sector opens a hanok getaway where Yoon-seo's team and Ju-won go for a business trip.