Gotta agree with you both here...
It's clear as day that the game exploits the male senior mentor and junior female protegee(s) trope and it's probably more central to the story than BDSM. With a distinct twist, but still. To add to your characteristics of these supposedly adult women, take note how a lot of them are sexually inexperienced or underexperienced, with repeated fetishization of their surprized reactions when touched by the MC's expert hands. The 'sluttiest' of the girls, Amy still has a lot to learn from Sir.
Is Newman really that grown-up? She's been in the forces and falls for the towel trick like a recruit in IET. And those doe eyes when the headmaster theorizes about natural sexual responses to painful stimuli in women, while he fingers her after spanking. Mind you, the sex scene with her happens after the shrinking potion scene, so you get to visualize her as a youngster before the MC fucks her.
Lucy the closest to being an adult? She still needs a shower, daddy... And do the chores so she may get her weekly allowances.
Amy and Liz are both embodiments of sexually maturing (but not mature yet) young women, who - while not silly little girls anymore - still need daddy's wisdom and guidance. Amy is the naughtier of the two, while Liz is a softer version. Notice how the MC constantly knocks Amy down a peg or two: she runs too fast, she uses inappropriate language, she's too horny - typical daddy's concerns. Liz also should moderate her enjoyment of nudity, there are evil people out there who might take advantage of that, just look what you did to me. Sounds like a dad (just disregard the erection) worried that his little girl is not that little anymore.
There are grown women in the game, but surprise! surprise! the MC does not have sex with them, even if he tries. Is that work in progress? I don't know, but suffice it to say that Trixie manipulates him into getting her a job and that she's the lead when blowing him. If he asks (yes, the master asks!) for sex, she flatly refuses and that's it. You/she can edge him to infinity, yet he won't be able to fuck her the way he can fuck Amy and then dismiss her 'I have some important stuff to do.' or 'Run now, don't be late to your classes.' Ms Chang just ignores his magnificent cock like 'boy, do you know how old I am?' while Ruth... Ruth is a conservative (read: sexually repressed) mother figure and conscience in one. She knows exactly what he wants, the way a mother knows when her boy's balls drop, trying to suppress his urges at first and then resigning herself to the fact.
The twist then? The MC is 36 and single... No mention of former relationships, apart from dreams featuring his former pupils. Instead, he brags about reading a lot.
I met lot of acquaintances, even friends and relatives, who had or still have partnerships with an age difference between 10-30 years. Your theory 'that there is someone a daddy (or also mother were the women is older)' in this setup is just wrong. Sure it is possible, but I never met such a pair relationship you described.
You've met a lot of people with a generational+ gap between them and you think the relationship dynamic is just as between peers or almost peers? My father is 25 years older than me and my mom was 27 when she had me. To put thing in a cringer perspective, imagine this - if I may use one of Louis CK's jokes - a 25-year old man looking into a pram and saying 'One day, I'm gonna fuck this baby.'
Especially pairs who are ~25+ and older you usually see not much differences anymore between them if there is a big age gab.
Imagine a 35yo man's wife who is 25 years older than him. She's 60, well past her menopause. He's in his virile prime. She has to wear glasses, perhaps even hearing aids. His senses are still acute.
Age does matter. Arrive at forty and you'll see.
