>>538561803
The purple swordsman already has all her books, the magic swordsman on the far right also only had one skill to trade for the book and doesn't care anymore.

The only one left is thief lady and apparently neither of those are sufficient. I'm at the last boss but theres still places I can't reach because they're too high or a weird hole, so its probably a normal swordsman book i'm missing for her.
Damn my completionist autism.