...or the rest of the staff just aren't utterly oblivious to the continued... particular tension of their interactions. :v
Yeah but Moe was talking about dating specifically. Even if they had noticed the tension between them, they probably wouldn't be talking about dating. Moe would say something like "hey, you think Risa fancies Aya" or something. Just like right before that, Moe said that about Miyu liking the kick boxing instructor "this way".
But I mean, this is what makes the most sense imo. They could still be over right after college, then Risa and Aya being just fwb during gym, then Aya getting married etc.
Also an interesting aspect of Aya and Risa's dynamic is that, considering Aya's personality, I think she wouldn't date a woman on her own initiate. She seems pretty traditional nonetheless her preference, and into the typical marriage stuff.
We could see that she was still torn about dating Risa or not recently. Risa being persistent with her is the key of why they might end up together. If Risa wasn't like that with her, I think Aya would eventually find a husband and probably be unhappy.