闇祓
Author:辻村 深月
Page count:416
Natively level:闇祓 | L30??
Summary
Japanese
「うちのクラスの転校生は何かがおかしい――」
クラスになじめない転校生・要に、親切に接する委員長・澪。
しかし、そんな彼女に要は不審な態度で迫る。
唐突に「今日、家に行っていい？」と尋ねたり、家の周りに出没したり……。
ヤバい行動を繰り返す要に恐怖を覚えた澪は憧れの先輩・神原に助けを求めるが――。
身近にある名前を持たない悪意が増殖し、迫ってくる。一気読みエンタテインメント！
English
There is something wrong with the transfer student in our class…"
Mio, the chairperson of the committee, is kind to Kaname, a transfer student who does not fit in with the class.
However, Kaname approaches her with a suspicious attitude.
She suddenly asks, "Can I go to your house today? and appears around the house. …
Mio is terrified by Kaname’s repeated bad behaviour and asks for help from Kanbara, a senior whom she admires…
The nameless malice that is close at hand multiplies and closes in on her. Entertainment in a single sitting!
(automatic DeepL translation)
Availability
Amazon, Bookwalker
ebook: yes
Why do you recommend this book?
This came recommended by people in this forum whose opinion I respect 
Apparently the tension is high and it gets quite scary. The author is 辻村 深月, who also wrote かがみの孤城, a very popular book in this forum.
Reading Sample
Read the first 30 pages on Bookwalker