小三往往是电视剧的男主角
[xiăo sān wăng wăng shì diàn shì jù de nán zhŭ jiăo]
'Xiao san' literally means 'The Third Younger', it's used to describe a mistress, usually in a love triangle relationship. In this context it humorously implies how often villains and mistresses have become leading male actors in Chinese television dramas.