Even if he’s living in the US, Tae Kyung’s dad wanted to keep tabs of the goings-on with Tae Kyung’s life. So, unknown to Tae Kyung, his dad and Pres. Ahn had been keeping in touch with each other due to this reason. During the process Tae Kyung’s father had swapped some stories about his step son whom he believes is as talented as his son. Because of these stories Pres. Ahn has a hunch he’s found the right candidate up to that task of replacing Tae Kyung. Now, all he’s left to do is convince this guy to go to Korea and be a member of his A.N.Jell group.
Hwang Geun Suk, (Yes, you read it right. His last name is also Hwang since Tae Kyung’s father legally adopted him and his sister when he married their mother) has a tomboyish sister Hwang Shin Hye. Her sister idolizes him so much that she does whatever he does (now, you see why she’s become tomboyish ) and goes wherever he is. This then leads us to these two conditions which Pres. Ahn must comply with before he agrees to join A.N. Jell. First, Shin Hye gets to live on the same house as him — meaning same house as the A.N.Jell and said sister of course gets her own room being the only female in the house. Second, that no one will know that they’re Tae Kyung’s step siblings. Since Pres. Ahn desperately wants Geun Suk to come aboard A.N.Jell, he concedes to these arrangements.
So here’s where the conflict begins. These two new additions to the A.N. Jell household does not know that this current Go Mi Nam is a girl (Go Mi Nyu) and twin sister of the real Go Mi Nam who’s now in the US recuperating from an injury. On the other hand, the A.N.Jell does not know that the new guy in the group with the tomboyish sister is actually Tae Kyung’s step siblings both of whom Tae Kyung’s never met before.