As for NTR conversations - I'm not a fan of it personally - I understand kinks for each are different so there's no judgement one way or other.
I think the game here doesn't need a bunch of it to be successful.
On the other hand, I'm not opposed to letting some exist if it's avoidable. Alexis scenes were avoidable. If you're playing the game and you're paying attention, you should be able to pick up on the clues that the dude she was flirting with at the table, and knowing your previous run with her ended due to her cheating - it's fairly obvious that was gonna happen if you didn't speak up.
I think there are some characters who make sense with - others do not. The definitely NO include: Bree, Hanna, Lavish, Shiori, Kylie, Cassidy (once you fix her mean daddy issue and she is dedicated to you). Samantha (if she left Ryan due to cheating to be with you), Palla if you're treating her well and helping her with manager etc.
I would like to add Lexi to that as well - I know she's a slut when you meet her, but there's some story and dialogue setting precedence that she sees MC as her prince that finally saved her from that life and she is spun on MC. So it's a special feeling kink to think you've tamed her from wanting to be a slut to only wanting to be with MC.
Those who make sense: Alexis, Sasha (if you cater to her 3some idea), Samantha (if you cater to her 3some idea), Audrey (is a major slut), Palla (based on story), Aletta.
Kleio, Anna, Morgan with each other.
To implement, it would be worth considering for some characters (Audrey, Aletta, Palla, Sasha, Samantha, Alexis) to add a new "points" mechanic like the LPs and GPs, called "Cuck Points" That way - the MC player has full control over avoiding or allowing and for whom.
BUT.....since it's safe to say MOST people prefer to avoid or not interested in NTR, it's worth pointing out that by adding this content, its using time/resources of the developer to cater to a smaller group of fans and taking away that time adding other content more appreciated by the general public. SO if it was to be utilized, the hope and realization is that it should be very little at a time and for those who are fans to not expect fast additions and developments because that simply isn't good sound choices on the Dev's part to cater a lot to it.