The Main conflict in this story is about him getting past the problem of girls constantly using him to get to his brother. He doesn't need to learn that people can just be platonic because that's not his issue. Hell he was very ready to accept them just being platonic.
What she does represent...
She's talented and hopped jobs, but I suspect most of her money went into her passions just because she was always impulsive and just making what came to mind and then none of it sold.
It's only after the series started that she started thinking about people's needs. Especially so after making...
Hm, I wonder who that apprentice could possibly be. Definetly not the girl who is certianly much stronger than one could reasonably expect with self-training
He also made an assumption about why. He's projecting his view of humanity onto her. He believes whole heartedly the only reason she killed the corpse of her brother was to aquire him. When in reality she has never mentioned aquiring him, she's just been moving in for the kill never once asking...