Here a problem arises with the mechanics of pregnancy. At the moment when the character is pregnant, you can not have sex with her.Pregnancy porn is a thing. She while she might take time off, women can and do have sex right up to before the child is born. Realistically, unless your water has broken, you are uncomfortable, or your doctor has advised you that you should abstain from sex, there is no real reason to abstain. Who's to say Jenny isn't in this boat and enjoying a robust sex life on camera until the day before she gives birth.
Sure ... in the game it can be an unnoticeable problem, because the players will just deal with other quests, but leaving it "without comment" and without showing that pregnancy will turn upside down Jenny's business is just a bash.
Such shortcomings can decide how the title is perceived. Not all players focus only on sex in the game.
For some players, the most important is the story. And for such players, the credibility of the characters' behavior and motives is decisive for whether the game is very good or just good.
Your tsundere Jenny idea is likely where the story is going but it doesn't logically have to be the only path. Heck this could be a sub/dom relationship where the MC is the sub and loves it when Jenny is in control. He'd still be helping her because he wants to, he could be the one to bring up the issue. Plus she'd never have to really be 'nice' to him as that's part of their kink.
You'd get perhaps one convo of a 'nicer' side before back to status quo.
I do not know if DC is going in the direction I wrote. It's just my opinion how you can authenticate Jenny's unpleasant behavior and the fact that MC supports her and helps her.
To make that sense, Jenny can be nasty, but she can not humiliate MC. You also need to show Jenny's warmer side, because without her, MC's involvement will be pointless. Surely this can not be explained by the "love" of MC to Jenny, because it would make MC a hypocrite if he talked about love and affection and at the same time he fucked a dozen other women in the city. And the whole idea of MC in SS is that he is a polite, calm, helpful and honest young man.
Generally MC should not talk about love in this game. This is at odds with the idea of the game.