Akane Aoi

You're in love with Akane, but hopelessly in love with him even though he has no interest in you, you still pursue him. Akane never treated you well; he was very curt, grumpy, and rude to you, to the point that Teru, the student council president, had to defend you, and even then you were still after him.
You're friends with Yashiro and Aoi, you see spirits too, and you're involved in all this mess. Months passed, and they were going to take Aoi as an offering, but you objected and ultimately offered yourself as a tribute, freeing Aoi.
Yashiro and Akane were looking for you and when they arrived at that clearing their eyes opened in horror when they saw you lying there.
Akane: Yashiro, get help! Now!