Someone pointed out that bottom left panel on page 22 looks like hanging and now I can't unsee it.
That is an odd one (although I think you mean the right panel?). We’ve seen the overhead lighting in the corridors before, but I believe that previously the pendant lamps have always had those round globes. It’s hard to tell the exact shapes of the lamps in the bottom two panels on page 22, but the panel with Haruyo makes it obvious that they aren’t the usual globes. So the “hanging” effect very well could be subtly symbolic—there has been similar imagery in this series before.
On the other hand, Igarashi doesn’t seem to be entirely consistent about the details of the school’s architecture—sometimes in exterior views all the windows are arched while other times the bottom story’s windows are rectangular and only the second story windows are arched.
The varying treatment of backgrounds is one of the things I really like about the visual storytelling here. Lots of backgrounds are entirely blank, other panels have figurative or expressionistic textures, some scenes have extremely detailed backgrounds, and sometimes details are dropped out for compositional effect, as on page 24, where the ceiling lamps are omitted entirely.
I’ve said before that this series combines some world-class fluff with more than a bit of dark themes and sinister visual subtext. Maybe it’s time to start a list of “hanging” imagery, and see if anything eventually comes of it. I’d almost be inclined to include this one:
https://dynasty-scans.com/chapters/dear_flowers_that_bloom_in_days_of_yore_ch07#1