Comment by VetusVulpes on Bie

@Bie Seo-in's brother is d3ad. The guy at the end is the actor who was working with Yeongwoon in the beginning. He and Seo-in used to meet up if you remember that's how Seo-in and Yeongwoon met again and that why Seo-in called him "babe" sarcastically. He's the one who's blackmailing Yeongwoon 

Hope this helps, I'm sometimes lost too since they look similar