盛世鹿晗
[shèng shì lù hán]
This refers to Lu Han (鹿晗), a popular Chinese singer, actor, model, and former member of the South Korean boy band EXO. 'Shengshi' (盛世) signifies a golden age or period of prosperity. Therefore, this username is probably used by fans of Lu Han who praise his glory days or express admiration for him.