Why does my boyfriend’s female friend look up my Instagram story?

So I noticed when he posted me a few weeks ago, which he does often since we dated, some of his friends including this one female friend from one of his volunteer groups decided to look me up and read my story most likely curious to see who I was. The thing is, he didn’t post me today or yesterday or the day before and this same particular female friend read my story just now. I noticed some people I’m not friends with do that to me but this one person is someone I know is his friend. Why would she decide to look me up and read my story?
Why does my boyfriend’s female friend look up my Instagram story?
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