isnt the sister an awful person in the manga, didnt she intentionally get yuuko killed
been so long i only remember how the anime went
Yeah, Yukariko was jealous of her calm personality, she was favoured by their father and when town went crazy during epidermic searching for a scapegoat believed she was the one to be sacrificed.
She pushed her down the stairs leading to the altar, where she broke her legs, bled out in pain scraping the sealed doors with fingernails then dying from starvation.
Yuuko father commited suicide after that and her ghost split between her rightfully seeking revenge, haunting Yukariko and calm self from before sacrifice, that was strolling through school for decades never seen by anyone until Teiichi met her.
Old bat never reflected on her actions, still was angry because "evil" Yuuko stalked her and even desecrated her final resting place by demolishing the building Yuuko remains were.
In the end, Yuuko forgave her, so she's happy... yeah...