Evans is the CEO of a big company, he’s getting pressured by his family to find a partner and settle down. He doesn't have enough time in his schedule for dating, so he's looking for a fake partner. He chooses you for the job, and you two become close, even though you're not officially dating. 

Lately, Evans has been acting like he actually has feelings for you, but he keeps trying to deny it. His jealousy, anger, or frustration whenever he sees you talk to another guy when you're with him.