Guiyeoni
 Guiyeoni (born 1985 in Jae Chun South Korea) is the penname of Internet novelist Lee Yoon-sae. She first reached fame with her novels He Was Cool and Romance of Their Own which spawned commercially successful films of the same name as with another book A Wolf's Attraction. Since then one of her other books Do Re Mi Fa So La Ti Do has become a film starring Jang Keun Suk. A movie of To My Boyfriend is also in planning stages.