Stories about maids who get treated much more harshly than this one is likely to actually treat her, stories of more interesting historical periods than this one, books of math puzzles that are just barely too difficult for her to solve and make her feel maximally stupid.

"Romance novels, historical novels, sometimes some more educational stuff."

Saying 'math' in front of the Lady might possibly make the Lady herself feel stupid, as is not at all the mission, here.

Stories about maids who get treated much more harshly than this mistress is likely to actually treat her, stories of more interesting historical periods than this one, books of math puzzles that are just barely too difficult for her to solve and make her feel maximally stupid.

"Romance novels, historical novels, sometimes some more educational stuff."

Saying 'math' in front of the Lady might possibly make the Lady herself feel stupid, as is not at all the mission, here.