i there some sort of story that goes with this?

Hmm . . . Do あなた mean like how a lot of people think Rose and Scorpius should be a couple? If so, then . . .
Well, nothing was 発言しました directly in the book, but in the epilogue, there was a part where Ron tells Rose to "stay away" from Scorpius. He also states that "Granddad Weasley would never forgive あなた if あなた married a pureblood". A bunch of people (including myself) think that this is hinting at a relationship between Rose and Scorpius. あなた know, irony または whatever.
I hope that answered your question!

I definitely think there is a story there