I don't really wish for artifical bs drama, but how Carol hasn't noticed Sara getting closer to her 'boyfriend', or her boyfriend spending so much time with his favourite teacher is a bit beyond me. It's all working a bit too flawless so far, while all the tension and drama keeps brewing in the background like an omnious storm cloud that might or might not be heading our way.
And even worse, and I know this is literally the single biggest worry of every single reader of this VN: The MC should really study some more!