The Poppy War

I really liked Rin's growth at the academy and the focus on morality and loyalty and struggles in war. I knew to expect the horror of chapter 21 and the details of the massacre so I could wait and read that when somewhat ready. 

I was not prepared for Rin to seemingly be 90% motivated by sudden lurv and grief and revenge specifically for Altan when she decided she wanted to destroy the federation - Golyn Niis didn't matter, the rest of her people didn't matter, just Altan mattered - as if her characterization in the rest of the book was just “this is her, but she'll forget because of sudden desperate love for him I've not shown before, she's fine with accepting this terrifying power upgrade and shrugging off the consequences (and the understandably appalled reactions from the other people who know her) for a boy.” 

I'll have to decide if I want to read the rest of the trilogy - and I'd definitely planned to go straight on, before the last two chapters twisted her into a sudden boy-inspired genocidal revenge fit.