I've been planning on getting into this series myself in the near future.
Amusingly, the show is co-produced by Toei Animation, though the studio doesn't actually do anything regarding the actual key or in-between animation.
I watched season one on ADN. Also read the comic.
On the other hand suscribing to ADN costs about 5€ per month and you should be able to watch this in only one month ;-).
It's quite nice but season one really ends as nothing about the story is solved. It really needs one or two more seasons to conclude (and indeed the comic consists in three books).
A coworker of mine started watching it with his kids, but had to stop because the younger one was having nightmares. I should ask him if he went further.
The video that was linked in the OP is very interesting, but is about the comic. It contains many spoilers if you intend to watch the animated series, and of course these two works are different.
Edited by gropcbf on Jan 11th 2024 at 10:06:48 AM

For those not in the know, this was a series pitched back at Cartoon Forum all the way back in 2019. It's based off a comic; sort of similar to Hilda The Series in that aspect:
https://www.studiolacachette.com/le-college-noir/
"In a small boarding school lost in the middle of the Cantal mountains, five teenagers spend the Autumn holidays with their jaded supervisor, Lena. But when they accidentally get cursed by a terrible witch, all hell breaks loose and the terrifying creatures of French folklore come after them…"
More info can be found in this extensive video I just found wile researching, which also happens to have Google Drive links to English scanlations of the original comic in the description:
Seems pretty extensive already, but the original reason I wanted to bring attention to this series that most likely won't be exported to the USA or dubbed in English is because a mutual of mine is currently fansubbing the animated series on Tumblr
: https://lecollegenoirsubs.tumblr.com/
https://linktr.ee/MalcmanIsHere