
tbh, i feel like there's something about that's girl doctor and how she wants to maybe make the grand duchess jealous over her and the grand duke when there's nothing

Well in the family, incest was a common practice, so by the context it seems like this new chick was supposed to be the dukes arranged wife way back when. I'm sure she's gonna try to cause some sort of problems between the main couple and ultimately fail. Since their relationship and feelings for each other are so slow pacing, I'm sure this chick is just a plot device to help speed up the realization that they love each other process. ╮( ̄▽ ̄)╭
Either way I'm for it if it means we get to see some lovey dovey moments between them finally lol.
ADOPT MR. FROG PLS