I'm looking for stories about characters who suddenly develop a strong conviction or just have a hill they're willing to die on (literally or metaphorically)–preferably about something seemingly mundane or unusual, but something more obvious like politics or religion would work too.
For example:
Bartleby the Scrivener by Herman Melville
The Vegetarian by Han Kang
The Silent Period by Francesca Manfredi
by foundryfoundry