I don't think that sex has anything to do with the story...let's see being a dick ...it has story sex both and it went out pretty well for the first 2 seasons because it has good story beside sex part....Third part he messed up, he got short on story and that too lame one.
Here people do like the story..Now for a second imagine Ana did sex with Chris is the last update instead of blowjob...Don't you want to see how it'll happen with Marvin and how the story goes on? Everyone would be waiting for the next update that way too. Because the story is good.
Now it's on developer, how long he'll decide to troll...For me even if Ana would have done sex with Chris, it would not be boring to play the upcoming updates at all to see how the story ends. But now whatever reasons he give to hold on to that sex scene I find it bs..I mean if you know how MP defines Ana character like she has daddy issues, she thinks her husband cheated on her, she's wet all the time, she gave bj to Chris where she doesn't even like that with her husband..She prefer sex over bj. Additionally, she's attracted to few antagonists, and she feels close to share with /enjoy being groped by other few antagonists...Now whatever reasons he will give beside that is trolling(,not the story part but the reason to hold sex).
(TL;DR I don't think we're far off base but I may not have been clear in the past, I later explain but this is a very long post. My bad on that).
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In the general sense you're totally correct, no disagreement at all. However, there are things a story needs to maintain pacing...and pacing is important. Not just overall story but character pacing. I'll try to explain in more detail than before because it seems like I keep having to repeat this (I blame my own lack of clarity more than anything or anyone). Let me try to fully explain and maybe you'll see that we don't disagree but are likely focusing on different things.
*This will be long but I read your post with true consideration so I hope and you'll read and consider mine*:
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First, a story needs backbone (often called other things like foundational theme) and characters need footing for a complete story to make sense and sit right with the person taking it in. A few examples:
Footing:
I don't care about Star Wars but I've seen the movies. Before The Last Jedi came out Mark Hamill went in front of every camera he could find to tell people that this is *not* the Luke Skywalker he knew and played. He even did it on the red carpet at the premiere! Later, many fans hated the movie and cited Luke as a major reason.
What happened? The writer of that film changed the footing of Luke. Luke was no longer Luke as fans knew him. That makes a story worse.
Another quick example or hypothetical would be if a new Iron Man movie came out and it spent the first half of the movie showing Tony Stark learning Algebra in order to build a tool he needed, lol. Fans would understandably be upset to have to pretend that "Supergenius, Tony Stark" didn't know basic Algebra. We've seen him time travel and build a suit from scraps in a cave but he had to learn Algebra real quick, lol.
The footing of the character would be destroyed by that. It would undermine the basic sense of that character.
Backbone/Foundation/themes:
Star Wars is generally about rebellion, teamwork, overcoming great odds through perseverance and faith, redemption, etc.
Sex wouldn't be one of those things, lol. Sex is, at best, a vague and distant theme and kept only to Han and Leia. Sex is certainly not a theme of Star Wars.
Ok, now to APM:
Sex *is* a theme of this story. This is a porn site, lol. Every story here is heavily and often totally rooted in sex. Sex is a backbone, a foundational theme of A Perfect Marriage.
So now we have character footing:
Chris (only speaking of Chris and Anna at this point) is a man long obsessed with Anna. He has lusted after her and been secretly in love with her for, what, a decade? Since college/University.
He makes his move and slowly flirts with her until she reciprocates. He sets his best friend up to look like a cheater to help his cause with Anna. He gets her to talk privately. He gets her to divulge secrets. He gets her to send sexy photos. He finally got her to jerk him off in a shower as he fondled her tits/ass, cumming in her hand! Then within the next day (or two) gets her to suck his dick in her garage!
It would go against his footing to suddenly pull back from pursuing Anna further. He is locked-in to a pattern of behavior.
Anna has lost her ability to say "no" to Chris. Clearly. It would go against her footing to suddenly decide that things will pause or stop with Chris. Anna is locked-in to a pattern of behavior with Chris.
Note that I'm ONLY referring to those two. I've long repeated that what I'm saying does not necessarily apply to other characters because they all have their own pacing. In this story about sex...and in the pacing between Chris and Anna...they have to fuck soon to maintain pacing because breaking that pacing (backbone and footing) will make the story worse due to it being nonsensical.
This does NOT mean Anna has to become the town bicycle with every man in town if she fucks Chris soon. Noe does it make other events meaningless or more important.
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Now, this doesn't mean there are no ways to avoid it! There just aren't any ways to avoid it AND keep the story at the quality it is without a massive and difficult to write alternative. Maybe Chris gets bit by a bus or sent to Antarctica for work (lol)? Maybe Anna trips doen the stairs on ber way to fuck Chris and she's now in a wheelchair? Whatever. It CAN be avoided but it would be hard to do and not come across as bad writing/pacing.
The reason a story written with no sacred cows and a nearly impossible ability to predict the next moves is because it takes a FANTASTIC writer to achieve those things.
George RR Martin with ASOIAF/Game of Thrones is an example and there are no GRRM-level writers making porn on F95Zone, lol. I guarantee. Its best for a dev on F95 to not even try.
So, had Chris and Anna fucked would it ruin what happens with other characters? Of course not, in a general sense. In fact, I'd argue that they SHOULD HAVE fucked instead of a blowjob due to the previous shower scene. But anyway...
It wouldn't ruin the story to delay that event but it would weaken it, and if you make that a pattern (like AWAM) it would ruin the overall story. I'm sure of that.
Again, even in a porn story that requires some leeway of credulity, things have to make sense and characters have to behave in a consistent way or the story is worsened.
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Finally, I don't claim to be the arbiter of everything. In fact, if I don't know what I'm talking about I tend to shut the fuck up. With most things in life I don't know what I'm talking about, lol. I'm not a "have an opinion just to have it" guy.
I will extrapolate if anyone asked me to but I've stated here many times that cheating is something I have personal experience with. It fucked my life up and I'm literally on this site due to that event. If I were still with my ex-fiance' I wouldn't be here or know what this site is, let alone be a member, but I kinda shut my life off after losing the only person I ever loved due to my own actions. That led me to being lonely and finding this site (I need to get back on track if I'm being totally honest, lol).
If this were about gangbangs or 3-ways I'd keep my mouth shut due to having never been in one. I don't know what a 3-way is like as I've never had two women at once...
...I know the pacing of two people having a fling behind the backs of their significant others. I know what that looks like, sounds like and the speed that it happens. No two are exactly the same but they all seem to share similarity so I think that's why I'm so insistent on this one is (Chris and Anna). I've never been a 90yo man (Marvin) and I've never been the head of a company that employs the hot daughter of an old friend, lol.
I have come across an old crush later in life, slowly flirted, slowly took breaks together, slowly left campus with them on breaks, sext, get nudes sent and fuck that person behind the backs of our partners. There is a rhythm to it. You don't pull back.
I've also taken courses on screenwriting and read a dozen books on the topic so I think that's why I also focus on the stories and pacing of VNs.
When a VN is going as well as this VN I don't want it to suddenly go to shit. Too many do, for dev greed or laziness. My takes are only an attempt to keep this going as well as it has been.