As
SecretD says, the winner is the Granny
And the winner is... Olivia, the Granny
She's been mentioned in 0.4.5 (not published on this site yet, right now it's Patron-only content. It will be published here and at itch.io during the weekend.).
It's not a realism thing due to her age. She's only 66 after all, and women older than her have delivered babies. She won't get pregnant for HER own reasons.
Think all the girls in the game have, at the start of the game, at least one issue that some sectors of society mark as a flaw (some of them aren't known yet). I don't share those sectors' views. Some of them are:
Martha is depressed and has a (very little) problem with alcohol.
Norah still sees herself as a fat woman
Emma is a possessive spoiled brat (with a questionable taste for color choice

)
Daphne is the typical nerd who, if she was a boy, would be planning on living in her mother's basement all her adult life, only studying and playing videogames and D&D
Erika had a gothic phase, derived to emo, returned to gothic and now she doesn't know who she is. Also, she has a lot of self-esteem problems due to being dumped twice for not wanting to have sex.
Scarlet is half deaf
Eileen has an alcoholic and violent father
Samantha is a workaholic
Simone has an overprotective brother
Olivia, the granny, has her own issues, and one of them has to do with not being pregnant anymore.
MC's role is, among other things, to help them overcome those issues, in some cases with the magic wand between his legs

.
Or do you think that 10+ sane bombshell girls/women will accept being in a harem with the MC? He is a nice guy, whose best quality is to know what to say to every girl for her to feel unique, loved, and worshiped, but he isn't the sharpest pencil in the box, nor is he perfect in any way. He has a naïve vein as has been shown in the bathroom fight (He thought Jack would be a gentleman and confess. once he was caught) or in his relations with the girls (He never thinks that they may be in love or falling in love with him.)
I'm also a nice guy, and I don't have a harem

(my wife is reading this over my shoulder. I love you, honey

)
About the harem girls not fighting, do you think someone like Emma will share willingly?