I agree we didnt get enough to know what their relationship was like but I think we're giving Kaede too much credit for Akane's success. All we know is she gave advice to talk to her mom. The rest is regular relationship stuff and Akane's own achievements-actually getting in and passing exams...
"I'm hollow"
"She was alive..all i felt was envy..i wanted to be her"
"It was exactly as I wished that she and I would melt together"
"With her I finally gained true life"
Kaede substitutes her hollow inside with other people's ambitions because that's how she captures the feeling of being...
Yeah some of y'all are illiterate.
No duh murder is bad, this isn't a murder is okay if you're traumatized enough story.
But I like Aka still even if he sucks with ending.