That's some future dad practice for the protagonist right there. Akihito getting along well with Emma is cute and all, but I'm also worried this might overdo it and become her childhood crush. Better if she becomes a wing girl for her big sister.
That scene about Charlotte distancing herself, because she was afraid of him noticing her sweaty smell was a typical romcom misunderstanding in the making, but I'm pleasantly surprised it actually got addressed with proper communication.
Why was I not surprised they turned out to be neighbors? So convenient, nevermind the seeming lack of a language barrier because they're also both seemingly perfectly fluent in each other's languages. Might as well have Charlotte be a Japanese girl or a hafu born in Japan, it's like she was British only to tick some fetish checkbox (exotic foreigner girl heroine).
On the bright side, that also greatly simplifies things for a future relationship... Sensei seeing the big picture here trying to play wingwoman.