The drama centers on the romantic and comedic interactions between Shim Bo-nui, a woman who has blind faith in superstitions and fortune-telling, and Je Soo-ho, the CEO of a game developer company who is a scientific and logical man.
A 26-year-old attractive woman who can learn quickly. On the other hand, she is blindly superstitious. She always follows the divinations of shaman Goo Shin because she is told that she was born unlucky. The shaman tells her that in order to save her sister Bo-ra, she has to sleep with a man born in the year of the Tiger. She meets Je Soo-ho, and coincidentally, he was born a Tiger.
A 31-year-old man. Born as a genius, he is a very logical and scientific person, who does not believe in anything supernatural. He is the owner and CEO of a game developer company, Zeze Factory. He meets Bo-nui, who asks him to sleep with her.
A 24-year-old man. A Korean with Canadian citizenship. He is a famous professional tennis player, and always places high in ATP rankings. When he returns to South Korea, he immediately searches for his first love Bo-nui. He has a strained relationship with his father.
A 34-year-old woman. The director of a big sport company that represents Geon-wook. She is Soo-ho's first love. Ever since she lost her older brother in a fire accident, she never shows her true feelings to anyone, and always strives to be perfect in everyone's eyes.
