Sonata of Morning and Dusk

[Classical Western Fantasy, single female protagonist, different world, sword and magic, slow-burn, non-travel] "You heretic! You were born to struggle in hell!" "Untouchable! How dare you disobey the most noble emperor in the world! Allowing you to live one more day is the greatest grace!" "Why are you doing this? People will not remember your efforts! The human world is inherently unfair! Join us! Overthrow it all! You will receive supreme glory!" … "I don't want to change the world! I just want to try my best to change things around me! The brightness of the day is not because of how bright the sun is, but because of how bright people's hearts are. The darkness of the night is not because of the departure of the sun, but because the darkness in people's hearts fills the entire earth!"