Strange Houses, Uketsu
Another mind-bending mystery from the author of Strange Pictures... This time, old house plans reveal something very odd linking two separate houses and a mysterious death. Uketsu does 'unsettling' right: the sinister implications that the two main characters uncover does all the work without any linguistic fanfare. Along with diagrams of the floor plans in question, this makes Strange Houses really quite accessible – which seems deliberate [1]
It's set up for a shocking, unusual reveal, though I still found it hard to suspend disbelief. Still, worth reading for the creeping atmosphere.
For me, it brings back memories of a misspent youth seeking out the creepiest horror comics/manga/novels, and occasionally finding something that sticks with you for a long time.
https://www.telegraph.co.uk/books/what-to-read/uketsu-strange-pictures-richard-osman-horror-japan/