Typographical comments
"And you... You never gave up on me, did you?"
Should be "And you... you never gave up on me, did you?" unless intended as two separate sentences
Same for "Good... Good..." slightly after that.
"All you can do is assure her that you will always stay by her side, that you are more than willing to help her."
Should be "All you can do is assure her that you will always stay by her side, and that you are more than willing to help her." unless a deliberate stylistic omission.
"The corrupted beasts of Minia seek more power and, even in her weakened state, Lady Sluttony shone line a beacon."
Should be "The corrupted beasts of Minia seek more power, and even in her weakened state Lady Sluttony shone line a beacon."
"She fought them to the beast of her ability"
Should be "She fought them to the best of her ability"
"Finally, on the third day, she was well enough to move."
Not technically incorrect but unless a pause adds some clarity a comma is generally omitted in modern works after the word "Finally" here.
"She pulled out a mostly-blank roll of parchment"
Should be "She pulled out a mostly blank roll of parchment", hyphens are omitted when adverbs are used and don't create a new concept.
"At least, the Half Elves don't,"
Should be "At least the Half Elves don't" This one is arguable as it could be said that the comma slightly modifies connotations of the sentence, but modern style heavily favors omission of commas after introductory phrases.
"But, sometimes, you'll find enemies that have really high armor."
Should be "But sometimes you'll find enemies that have really high armor." or "But sometimes, you'll find enemies that have really high armor." Introductory conjunction adverbs which are short typically have the following comma omitted.
"First thing's first,"
Should be "First things first," as the things are plural not possessive
"The goddess looks away, a small, sad, smile on her face."
Should be "The goddess looks away, a small sad smile on her face."
Comments:
"The once-goddess is so vulnerable right now."
Even though an esoteric distinction, this is correct. Nicely done.
Capitalization of races/species is generally not done in the real world, but sometimes it's a a deliberate stylistic choice for fantasy settings to capitalize things like "Half Elf" or "Dwarf". The way it's done in most media is without capitalization, (e.g. Dungeons and Dragons).