Hard to answer this without kicking off a hornets nest of harem discussions but at the moment (and if you're reading the in-game cues) it doesn't look likely that ALL three of them will agree to a foursome with their family members. Although (and I have mentioned this previously), I'm not ruling out some non-canon fantasy type epilogues/DLC after we wrap-up the main game. These DLCs will ignore everything we have set-up in the game and give people a specific scene that covers some non-canon scenarios.
I agree that it doesn't look likely ... without a little help from the plot.
Jenna has already started to work her magic on Katie, so I think that threesome is in the bag. The real question IMO is how would Monica get involved? I proffer the following four-part solution:
1) Reveal that Jenna and Katie are not Monica's biological daughters (and, if you really want to be pedantic, one could say there was an error in their adoption paperwork too).
2) During a lewd tryst with Jenna and Katie at home, Monica comes home drunk and joins in a bit (maybe just hand stuff and some oral).
3) Later, the girls have occasion to have a girls night and some heart-to-heart conversations about how MC makes them happy. Under the right conditions depending on MC choices, they agree to share. This allows for polyamory.
4) To get a foursome, would need to satisfy some other condition. I would propose not fooling around with any 'side' girls except for Jolina, Debbie, Lily, and Zarah due to their narrative roles in helping Jenna, Katie, and Monica, respectively, come to accept their lustful urges. MC would need to reject those 'helper' girls (i.e., Jolina and Bella stay together, Debbie and Lily get together, Zarah dies offscreen idk whatever) to get the epic foursome fuckfest ending. THE END?
The official walkthrough only goes up to Episode 22, and it hasn't leaked here (it's a $10 tier Patreon perk). Zoey discontinued his walkthrough after Episode 18 (that's the one linked in the OP) since the variables were too complicated for him to keep it up. We just have to wing it for now.
