If we were trying to make just a porn game, porn stories, films and games would be our sources of inspiration.
Our sources of inspiration are Mad Max, Fallout and other similar games, settings and movies.
Mate, there are so many people on this site who don't understand what porn is, so classify games with complex stories as "porn games", simply because they have lewd scenes.
It's as though "Ug me see pussy, game be called porn".
DeLuca Family, Rebirth, Reluctant Archon, Ataegina, Hillside, CoBD, Sorcerer, TFTUV, AHITR, Deliverance, What A Legend, Starship Inanna, Heavy Five, Callisto, Lord King, Vae Victis, Through Spacetime...
All have solid stories. All have been incorrectly described as "porn". You're in good company.
He's not an old fart at all, and considering how athletic he is it's safe to assume the MC is rather young.
It's not safe to assume anything of the sort. Quite the opposite, as a matter of fact.
He has a daughter in her early twenties.
Simple maths tells you (for a fact, not an assumption), that he's at least mid to late thirties (If he was 15-19 when he had the child), most likely early to mid fourties.
Being athletic is not an accurate indicator of age. Everyone here can see easy RL examples of men in their 50's who are immeasurably more athletic than some 18 years olds out there.
Hold your horses here, guys. I never said anything about that I dislike it. Just little bother, not much... And so far I know that Adult Visual Novel is just nice alternative to term "porn game". In most cases for sure. My GF will disagree with the nice description saying something like "Playing porn game again?"...
I'm afraid to say that both, you and your gf, are incorrect.
The fact that she describes it as such, just sounds like a sign of contempt for what you're playing, possibly because you're not playing with her, instead?
I joke, it's just a lazy, easier term to group anything sexually explicit under.
Regardless of that, in order for something to qualify as "porn" it has to be something where the plot (I use the word very loosely!) only exists to lead you to another scene containing sexually explicit material.
This game & many others on this site have stories which do not act simply as a vehicle to take you to the sex scene, the sex is more a natural part of the story.
The story would still be interesting, if the sex was removed. You cannot say that about porn.
Hence they are categorically not porn, by literal definition of the word.