Didn't expect the author to draw an actual table breakdown of the situation but it's very helpful.
Kinda weird that he does not even remember the face or name of his middle school ex though. I don't quite buy the Watanabe theory yet, because it's strange and doesn't make sense why he'd dissociate his ex-gf's identity like that. But I'll note him for now as Chekhov's femboy who I'm sure will be important later.
I'm sure both Haruka and Saki would love to get on that list. And Kazuya would probably love to add Akane to that list, but he didn't have it in him to put her into that list himself.
I don't know if it's some kind of karma that, because he keeps refusing unrelated girls who are practically throwing themselves at him, he gets his own blood-related sister to do the same as punishment.
inb4 MC is not a virgin anymore because his crazy brocon+shotacon sister has been molesting him since childhood
So...does this need an incest tag yet, then again there's no haerm/romance tag either
I'm kind of against adding the Incest tag because it's spoiler-y and we only get to know this around ~50 chapters into the story. But the Harem tag seems very applicable (Romance is doubtful, since MC has done nothing but dodge horny girls so far), and I'm even wondering why there's no Mystery tag when the plot supposedly revolves around figuring out what that mysterious number and message window is all about. But we'll see...