The author isn't even trying anymore.
It's been a directionless symbolism jerkoff-fest for the past 80 chapters.
Man is just writing as he goes while the ambiguity and potential for some reveals create this mask that the series is some sort of genius masterwork. It's like me in middle school media class trying to ham in as much special effects and glitch sfx to sound edgy and profound. It's so fucking embarrassing. This used to be one of my favorite mangas, and I still think the earlier portion of the story has some genuinely great story with actual substantial discussion to made between Seichi & his mom as well as how visual imagery is used so effectively.
Nowadays he's just mindlessly drawing for the sake of drawing and hoping that the fanbase he's created will eat this shit up like it's some high-intellectual "you just don't get it" masterpiece.
No, to me it really feels like he is writing from experience. Be it himself or someone he was close to in his life.
My life has been that of constant abuse, starting from a very young age, and this is the piece that encapsulates it the best.
If you don't like it, there truly is nothing wrong with not liking it. Different pieces will resonate with different people for different reasons. It does for me due to how much I identify with it all.
Fact is, people are gonna be stuck with these thoughts, feelings and memories for decades to come and it does come in such imagery. I am glad that someone is expressing it in a more realistic way. The way it affects your perception of reality and you aren't sure what is really real anymore. The dissociation that comes from it all, it's honestly quite realistic.
But yes I will say that if you haven't been through this dire of an abuse, you couldn't understand. And that's honestly a good thing.