Mana, an office lady in her 30's, was doing well both at work and in love. She was about to get married to her boyfriend, whom she was living with, but he cheated on her and they broke up. Wanting to change the things that just didn't go well no matter how hard she tried, she moved into a share house, but the inhabitants were people there who were not particularly easy to deal with... (Source: Akita Shoten, translated)

"I know the secrets of everyone in this class☆" That is how the twin-tailed new transfer student, Koto Tsutsunuke, introduced herself to the class. Her new classmates are shocked by her brash remarks. And the teacher is no exception to "everyone in this class"... Seeing her grinning face, the students realized… This girl is dangerous. Now, their ordinary school life is over, as everyone's darkest secrets become exposed. (Source: Kadokawa, translated)

A mysterious woman eats lost letters and resolves the problems written on them.

A comic version of "Scary Stories That Happened at School", a masterpiece that decorated the final days of the Super Famicom... ... but although there is an interview with the creator, the content of the game and the manga are not related. In 　fact, the article on the game is less than 10 pages long, including the interview with the creator... 　Well, it seems that this book was made before the game was released, so to be honest, it is a horror manga book that is unified with horror manga set in "school". 　However, since it was made by the world-famous ASCII, there is not even a trace of the cheapness of making it by gathering up some unemployed manga artists. It 　has a pretty luxurious (in other words, strong) cast, and there is a wide variety, from pure school horror to crazy horror.

https://www.cmoa.jp/title/331077/