It girl

An "it girl" is sort of like a celebrity who everyone thinks is really cool and wants to be like. She might be a famous actress, singer or model who is always in the news and people talk about what she wears or who she's dating. People admire her style and personality, and many people try to copy her in order to be as cool and popular as she is. Basically, an "it girl" is someone who is famous for being popular and cool.