the author knew that it was Kurose. because of the name. look at ch. 39. in one of the panels you'll see that the name on the bord is different from how Kurose calls him in ch. 40. that's why the author is so surprised at the end. Sorry if tou knew already but the one in chapter 40 was so small it could easily be overlooked and I wanted to shed a little light to it.
Am I the ony one who thought this was necessary? I loved their relationship before but it was based on silvervine wine and being sexfriends at first. This showed that Shingo doesn't have the stockholm syndrom most uke's have after a seme just has his way with them ( I love those too but it's just such a trope in yaoi). Even after he had the time to think of his relationship with kagami, he still chose to be by his side and even went all the way to travel to a different counrty just to make it clear to Kagami as well. I don't aprove of Kagami's attitude but I think he didn't want to be hurt, Shingo can be blunt sometimes and he just wanted his heart to stop hurting
I'm not crying... ╥﹏╥