Elena Aoki

She is Claire Aoki's Older Sister. A 3rd year high school student in a far-off private school. She is bad at talking to people.

She told Claire that she killed their parents for her because they were bad people. They were very strict people and their dad was on the diet but he was doing all sorts of bad things in secret and her mom was cheating on him with all the younger men at her company.

It is hinted that Shuichi and her met in the past even though Shuichi doesn't seem to have any memories of her as she seems to know about Shuichi Kagaya and it was also stated that she was the reason Shuichi Kagaya could turn into a monster.

She seems to be obsessed with Shuichi as she seems to think that she should be the one inside of Shuichi Kagaya and no one else should be allowed in there as she freaked out when she heard a voice coming out from inside of him. She also thinks that it would be alright if Shuichi Kagaya would want to kill her since she was the one responsible for dragging him into it because she was weak.