It's gonna be real hard for the mangaka to write a reasonable explanation for her turning him down and not explaining anything, but its interesting enough to follow
For some reason, I feel like it's going to be the ace attorney twist. The book loving twin died or something and the other one took her place out off guilt or something.
I might be crazy on this one but I think neither of those twins is his girlfriend in the future. The girl on page 5 who is looking at the mc and his friend might be the one. She might have changed her appearance in the future and the mc doesn’t recognize her in the past.