Hmm....since this takes place after the memory wipe in book 4, Suwako comments that apparently Shota can make contact with her when he's sleeping. Hope that mirino is working on book 5, because I want some damn closure to that development.
Edit: it looks like Mirino did a reboot of the series. He released a re-make of book 1 on August of 2017. Guess he wants to buy himself some time to figure out how he's gonna end it. >.>