(Spoilers about failed Areve ending)
I have a headcanon/theory about Areve, which is that she is afflicted with a curse that makes those who love her forget her when they don't stay in contact. The reason I think this is because of the failed ending, where she dies and you lose all memory of her, and also the dialogue where she talks about her hometown she says (approximately) "I was loved, I think, no that's not right, I was undeniably, certainly loved." and I was thinking about why she would doubt that the people in the village loved her and it could be because they would constantly forget about her because of the curse. Areve is also associated with forget-me-nots. Her failed ending is called "forget me not", the first lunchtime in the gardens with her says she's surrounded by forget-me-nots, and her picture in the student spellbook is framed by forget-me-nots.
I don't know if in the success ending she still dies but you remember her, that would probably ruin my theory (and also be really sad). Also can you tell I've failed Areve's ending too many times to count ;-; aaaaaa why is she so damn difficult. I'm using the guide I just don't know where the stupid student council is. Wish me luck