@tuatara1 The fact that I had to read your comment, to understand why he recognised her, means this is really lazy. Different hair length - this is on the same level as Clark Kent/Superman's glasses.
"Hina, I... always loved you... even as a man... I guess now I fell love with both of you"
Wouldn't be surprised if this were to happen.
Could also be that he says sorry for bothering him with his feelings.
I don't remember the exact chapter, but it was established a while ago that her breasts grew larger as she felt less like a boy / more like a girl. Which makes sense considering… well, no spoilers.
@UnholyPerson Well yeah, because Hina wanted to find the right timing to tell Kyousuke that she is Hinako, but missed all of them. And love hotels are usually drawn with see through showers (and prob have them irl), so she couldn't really take the wig off on the chance he was looking or caught a glimpse.