Yeah, that's a trope in porn, but it doesn't make for very compelling scenes, from a character writing perspective, imo.
To that I'd say "then you aren't trying very hard"
(or have something against the group scene)
And a mother/daughter sucking a cock at the same time is incest lol. Ask anyone who doesn't play too many VNs or watch too many 'step-family' scenes and they'll tell u straight up "shit's weird af". So, when u filter that through the characters, I guess I'm the kind of VN consumer that wants a somewhat believable interaction.
If the characters are just freaky, then ok, that can be believable, but why are they freaky? Maybe they have personality issues like dark triad, borderline, histrionic, etc. (each giving different potential motivations) or maybe a history of sexual victimization or drug addiction, stuff like that.
Be careful with that "anyone" buddy (your statement might be true for
many from the
vanilla scene but definitely not everyone (and "anyone") when you consider the full spectrum of kink culture and definitely not when you venture into the group scene), a Mother/Daughter threesome is no more incest than a Father/son threesome is (Have you never spit-roasted a girl with Pops?) so stop being sexist
.
BTW I don't agree that incest is as black & white as you seem too. I've been lucky enough to have had a threesome with a couple of sisters (sisters to each other, not me) and none of what they did with each other during that time counts as incest in my book or theirs (and they weren't shy about touching each other to tease me).
(I'm not open to debating this BTW, you have your opinion, I have mine)
I've come close to the mother/daughter fantasy in real life with a mother (40ish) & daughter (mid 20s) having some kind of girls night at my bar I think the Mom was getting over some kind of divorce/breakup and her daughter was trying to cheer her up (I was the Barman), I gave her the nice chat, "He's an idiot!", "You're beautiful!", "Any man would be lucky to have you!" etc... both of them flirting heavily with me .
The daughter was giving me all the signals that she was open to visiting the bathroom with me and I'm fairly sure that the mom would have tagged along whether she was invited or not (unfortunately in this case the mom wasn't particularly appealing to me or I might have seen where it went).
It's entirely possible they were playing and if I had made a move they would just have laughed it off (just girls playing the flirting game, more about affirmation than anything else), but like I said that wasn't the vibe I got, I'm also fairly sure I would have been welcomed back to their hotel suit by either (whether they would have been open to some 3some play in that setting is very uncertain, but alcohol + breakup + libido in a strange town with some fresh meat can lead to strange places)
FYI the best sex is a bit "Freaky", it's scary... out your comfort zone, the paranoid voice in your head is screaming "this isn't safe"..."it's a practical joke"... "it's be a trap, a setup to rob me"... "they could be crazy, I'll wake up with my balls nailed to the wall"...
What are porn games for if they aren't used to explore those freaky places, the best erotic writing delves into these dark/exotic moments that most people don't encounter in reality (and if they did, they would likely be too scared to explore).
PS, screw exposition
(not everything needs to be explained)... if you can't have the occasional wild stereotypes in a porn game where can you have them... IMO they work best when integrated with other more stable/grounded characters, Gina is a perfect example, I can totally imagine her mom being a Wild, Hippy, Free Loving, Maneating, Cougar who would either insert herself into Gina's love life (to educate her) or try to steal her lovers.
