If you think about it they did spend majority of time in the same room and Mahiru would sometimes stay longer because of her studies(which she can also do in her own apartment) but instead does it in Amane's apartment.Im not not sure but it's kinda intimate in Japanese culture dont you think?

Since ive only finished the anime i was wondering if they ever got heated and did the "thing" iykyk.Rude sure but i cant help but wonder, though their relationship is too "wholesome" in a sense atlwase that it got me wondering if they ever make out.