That girls name is Ramita Maharjan, hence she is from Jyapu community.Jyapu word itself  is not derogatory but some uninformed people do use this word towards Newars as derogatory or mocking word. I believe how you percieve this word depends upon the context. In the context of that pic, its not derogatory to use Jyapu Muskan. That being said, we are Nepali first then Bahun, Chhetri, Newar etc.