I'm sorry if what I typed is a repeat of any previous discussions that already have answers.
Hmm, the way Yakumo was able to tell that Haruka had a little sister that died instantly gave me the thought that Haruka's sister was following her as a ghost all this time, wanting to say that it was all right that the accident which lead to her death was not her fault, but she could not because humanity cannot see nor hear ghosts/spirits. When Haruka entered the room, and Yakumo getting some time, he was able to tell probably because he saw the little sister following her with his red eye. But at the very ending, well you know what happened.
The psycho-teacher was weak... What was the purpose he was trying to prove
or does he actually enjoy killing people for fun.
Still need more info about Yakumo before I can fully clarify my opinions about him
