I agree on the sex part between mc and Amelie on next chapter but I highly doubt that Amelie will be jealous with MC because he found a GF. I believe that she will be relieved that the MC has a new GF and that will take the heat off of her because the MC will focus on having sex with his new GF instead of with his aunt. She might even consider giving a chance to Davie to save her marriage seeing that the MC has moved a bit forward into looking for a GF. Lets face it, she is started to cross that line she drew little by little and she knows that at the end if things go the way the do they will finally end up having sex, but I don't think that jealousy of another woman will make her drop all reservations and go for ....IT with MC. I think that being frustrated and let down once more by Davie -in a future date with him - will be the breaking point for her. Maybe she will get a bit drunk like we have seen in the past and maybe MC will take advantage of her, because he is not the best example of a man that can keep his dick in his pants, with all kinds of consequences in the aftermath. And let's not forget that the game is planned to finish after what? 6 or 7 chapters? we still have a long way to go; I just hope that we will get to see some sex with Amelie in the next chapter.
I see your point, but from what you said I understand that you think (like other games) that sex with Amelie will end the story, but the DEV doesn't have this mindset.
For few reasons What you said wouldn't happen [unless the DEV decides to become an asshole milker]. to cast the players back to the starting point.
Otherwise to follow up with how he lays the story actually, Amelie is too hooked now to go back to Dave, she crossed the stage of saving the marriage, she already gave up on that when she heard him on the phone. That's one.
Second he already invited the family and she ended up in toiled with MC which shows that her mind is already set.
Third reason is the DEV is planning around 20 Chaps, and pregnancy. well personally I don't want him to give me a poster at the end with the pregnant Harem, and I don't think he has this mindset. Chap 11 is the exact sweetspot for sex to happen so that he can explore the rest without rushing things. I tell you this as narrator myself. But he might keep the scene at last part of chap11, to hook you more for another year of waiting hahaha.
Also delaying more than that will bring a hate wave that he's not ready for. It won't be good for his reputation either even if people will still be hooked.
If his skills don't block him, i'm sure he would manage some sex scenes with preggos way before the end.
So all the above considered, the next chapter is the sweetspot and his last post mentionning the "importance" of this chapter kind of tell the whole story. (again unless he starts to be an ass again and mess up).