While hanging out in a karaoke room with his friends, Bum-seok runs into the bullies from his previous school. Soo-ho makes them apologize, but Bum-seok isn't happy with Soo-ho ordering him around. Si-eun becomes more worried about Bum-seok who seems to be getting more unstable.

Bum-seok befriends with Jeong-chan and Tae-hoon, he reeks of alcohol every day. Si-eun thinks Bum-seok is being used by Jeong-chan and Tae-hoon. He also thinks Bum-seok is behaving that way because he is lonely. Si-eun wants to help Bum-seok, but Soo-ho thinks he's done enough. Meanwhile, Bum-seok pays Woo-young to beat Soo-ho on his birthday.

Si-eun gets beaten up by the guys Bum-seok paid to beat up Soo-ho. Si-eun gets seriously injured, but he doesn't tell Soo-ho about it to protect Bum-seok. Soo-ho finds out later and decides to confront Bum-seok. Bum-seok pays Woo-young again to beat up Soo-ho.

Si-eun and Young-yi get anxious as they can't get hold of Soo-ho for too long. After Si-eun finishes his exams, he hears the shocking news. Meanwhile, Bum-seok's dad tries to make Bum-seok go study abroad.