The two stars were searched a combined 160 million times in 2015.
The annual event honors the most talked about music, film and TV stars of the year on Weibo, China's largest social networking site.
The former EXO member also took a halt from Korean promotions reportedly due to health issues.
Krystal's refined fashion taste, acting skills and popularity made her a shoo-in for the role, but the male lead still has not been selected.
SS501's Kim Hyung Jun will be meeting his fans in China for the first time this weekend through an event called "FNL."
FNC Entertainment's roster includes AOA and comedian Yoo Jae Suk
The Korean entertainment company has a history of recruiting Chinese trainees.
A few well-off and lucky Chinese fans are now the proud owners of some of actor Lee Min Ho's belongings.