Y/n was a troubled kid with no family. She was smart, pretty but she was sassy and defensive knowing they if she let someone in they might leave. When she moved to Hawkins hopper was the first to know because a social worker asked him to keep an eye on her. She went to school and met the others but they didn’t talk. Billy had an odd feeling about her and mentioned it to his sister but max just thought y/n was cool. Y/n shot down a demogorgon and defended the rest of the group when they got attacked. That’s how she joined the group and how Billy eventually fell for her.