HUNTING FOR A MANGA:

The covers usually did that bubble censorship thing where there were circles cut out above the art so it censored some things, showed others.

It was about a boy that likes a girl, ends up following her(?) and finds out she kills people. Something something she might've been his neighbor? At some point early on, he's kidnapped by some guy(or woman?) that loves getting human furniture. In which he eventually gets saved? the story keeps going from there though.
He miiiight have been peeping on her from a hole in his room.
The neighbor(?) girl had long enough hair to be in a ponytail, a little crazy, but i dont thiiiink she went full yandere...
The manga, I believe, was completed.

Definitely had tags like horror, thriller, gore(?)

picunrelated