Kim Myungsoo is now one of the most successful bussinessman and maintained his father's company very well. After having a successful in his bussiness, he would make a party and invite all girls and his friends. He would call the one lady to his room to entertain him but he never sleeps to any women/girls. He would just make them fall asleep utntil the sun has rise.

Then one day, Myungsoo has stumbled to this little boy who claimed Myungsoo his 'appa'.... Is Myungsoo is really his 'appa'?????

1. Kim Myungsoo

The youngest most successful bussinessman who inherited his father's company, CHUKA. 

2. Son Naeun

She is working in old folks home and very dedicated. She is somehow tough and fragile at the same time, Her parents died at the age of 11. She left Seoul after her high school and bringing her child up alone in Busan.

3. Son Myungjun (fictional character)

Naeun's son and he is very lovable child. Myungjun is adored by the old folks due to his polite and well-mannered. Myungjun is indeed curious about his father. He believes his father is out there somewhere and determined to find his father.

4. Kim Jongin aka Kai

Naeun's best friend. He followed her to Busan and even give up his dream to be the singer. He loves Naeun but Naeun just treat him not more than friend but he's still hoping. 

5. Lee Sungyeol 

Myungsoo's best friend. Quite a drunker but very nice. He doesn't has any idea Myungsoo had relationship with NaEun.