Ohhhh now I remember the girl! Then yeah, it's a choice of necessity, I do hope that she will quit if MC gets the means to compensate and/or she becomes a central love interest, that said yeah prostitution exists, it's just very rarely shown in media, if anything GG for having the balls to piss of a few people to follow through with your vision of the game (P.S. though, there's netorare and netori, and both are from the MC point of view by definition, that's why people don't really complain unless it's netorare, that being said, complaining about there being soft netorare is definitely a bit much, especially if they like netori because that's just netorare to someone else, literally. I don't remember the relations between LIs, but sidenote that if they know about the other LIs and are okay with it it's harem and although I get how one could see ressemblance between harem and netorare/netori, there is a clear distinction (Unless, of course, there is another element that makes it so)
I didn't unlock the h scenes with Ayase so I'm not 100% about her stance but I'm pretty sure there is no real attraction there, Miharu gets jealous and upset when she sees you with other girls so there's that. Either way, why complain about it one way but not the other? Double standards. It's not even soft ntr. Nor is it cuckold in any way. It's just a character in a main friend role doing what she literally said that she does and gooners wanting exclusivity.
MC doesn't see her sexually nor romantically. The only time he does is if you choose to fuck her. Which is after she tells you her situation. And even then it is only in that situation. I don't believe the story really shows her in a way that you would want exclusivity at this point in the story. Later on however, MC might develop feelings. But that's obviously going to be WAY after you help her get out of that situation. So again, no ntr. No cucking.