Why did Grimm curse himself to be unable to wear shoes?
Here's a hypothesis and headcanon about Grimm from Sentouin Hakenshimasu.
The other day, in a debate with a friend, She asked me about Grimm's curse, and I told him that Grimm mentions it twice in the novel, but Rokugo either didn't pay attention or didn't care. My friend says that even if She didn't pay attention, it must be noted, just like Aqua is mentioned by Tilis even though Rokugo didn't pay attention.
That's why the omnipresent first-person past tense format takes me out of the movie.
What I'm getting at is, as far as we know, Grimm lost her ability to wear shoes when facing her greatest rival. Who is his greatest rival?
My headcanon is that Grimm ran into that childhood friend she liked, the one who had married another woman, and bought his wife some shoes. Grimm, in one of her frequent fits of rage, said to her, "Oh. You like shoes so much? Well, you'll never wear them again."
And then the curse rebounded. I still don't have enough evidence to prove whether the success rate of curses isn't pseudo-random, as Grimm claims, but rather that, besides the appreciation of the offering, it also depends on the intention.
This is already a fanfic, but Grimm starting with "About a while ago" and then saying "a few years ago" suggests Grimm is in denial or ashamed of her age. I think that in the novel, Grimm actually tells Rokugo her age off-screen, and Rokugo feels embarrassed that She's acting that way at her age.
My headcanon is that Grimm is nearly 80 years old.