Main •
Hwang Jung-eum as Shim Bo-nui • Lee Ye-seon as child Bo-nui •
Park Seo-yeon as young Bo-nui :A 26-year-old, attractive woman, who can learn quickly. On the other hand, she is blindly superstitious. She always follows the fortune-tellings of
shaman Goo Shin, because she is told 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. •
Ryu Jun-yeol as Je Soo-ho • Gil Jeong-woo as child Soo-ho • Seol Woo-hyung as young Soo-ho :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 also CEO of a game developer company, Zeze Factory. He meets Bo-nui, who asks him to sleep with her. •
Lee Soo-hyuk as Choi Geon-wook / Gary Choi • Hong Dong-young as young Geon-wook :A 24-year-old man. A Korean with Canadian citizenship. He is a famous professional tennis player, always placed 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. •
Lee Chung-ah as Han Seol-hee / Amy Han :A 34-year-old woman. The director of a big sport company that represents Gun-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.
Supporting ;People around Shim Bo-nui •
Kim Ji-min as Shim Bo-ra • Kim Bo-min as young Bo-ra • Kim Jong-goo as Goo Shin •
Kim Sang-ho as Won Dae-hae ;People around Je Soo-ho •
Jung Sang-hoon as Han Ryang-ha •
Gi Ju-bong as Je Mool-po •
Na Young-hee as Yang Hee-ae •
Jung In-gi as Ahn Young-il ;People around Choi Geon-wook • as Choi Ho ;Zeze Factory •
Lee Cho-hee as Lee Dal-nim • as Song Dae-gwon • as Lee Hyun-bin • as Ryu Ji-hoon • Cha Se-young as Ga Seung-hyun •
Kwon Hyuk-soo as Jo Yoon-bal ;Extended cast • Jo Seon-mook • Song Kyung-hwa • Jo Shi-nae •
Baek Ji-won •
Oh Hee-joon Cameo appearances •
Kim Young-hee • •
Park Sung-kwang •
Heo Kyung-hwan ==Original soundtrack==