Sorry eh, I don't want to go against you, but how can you say it's not NTR? What if the mother leaves and starts making porn films? Then anti-NTR? You opened a topic, where the aforementioned fetish is neither in the genre nor in the tags. If a love interest, gets stolen and ends up having sex with others it is NTR. The MC lose is LI. Now if you tell us there's a second ending, I hope it gets posted. Otherwise I doubt that the anti-ntr faction as you say will play it. If your idea is to find new subscribers to your patreon/subscrivestar, you also have to give them what they ask for. Otherwise why subscribe? Remember that those who play here are always potential future members.
At last i hope that this second ending is not like the first one. But with the mom who stay with her son and fuck always together and alone! No other men! I wait till this ending come here. Otherwise not.
Anyway thank you for post it. But till i am not sure that the ending can be "NO NTR". I do not try it.