2DK, G-pen, Alarm clock. - Vol. 5 Ch. 19.5

[MangaDex]

 

[muhandar]

huh ? isn't nanami's ex a male ? or maybe it's her partner before meeting the hometown guy. But then again what did mahiro mean that she (nanami) swing that way ? nanami doesn't even think it's normal for two girls to like each other (like thinking kaede as a lover potential). Did I mistake things or perhaps I wasn't paying much attention ?. And here I thought that mahiro knows a lot about nanami from her hometown ex boyfriend/fiance. Btw love this manga and thanks Gouma-Den for continuing this amazing series and in an outstanding update pace

 

[Engie_3]

huh ? isn't nanami's ex a male ? or maybe it's her partner before meeting the hometown guy. But then again what did mahiro mean that she (nanami) swing that way ? nanami doesn't even think it's normal for two girls to like each other (like thinking kaede as a lover potential). Did I mistake things or perhaps I wasn't paying much attention ?. And here I thought that mahiro knows a lot about nanami from her hometown ex boyfriend/fiance. Btw love this manga and thanks Gouma-Den for continuing this amazing series and in an outstanding update pace

This seems to be the introduction of another partner before the hometown guy she was in a long distance relationship in. Or at the very least I don't remmeber Shiori being mentioned by name at least. There is a chance she's the "underclassman from college" mentioned on pg.37 of ch.1 maybe, though it doesn't feel quite right.

Even as early as chapter 3 we see that Nanami is open to dating other women, it's just that she didn't think Kaede was her type (Mature girls with more distinct featuers, a "trophy wife"), as seen on pg.20 of ch.3.
Plus there was Nanami's thing for Mai, which she had no issues with.
So yeah, while it's never explicitly stated she seems to have been bisexual from the very start of the series.