In case someone missed how utterly savage she is.
All of her mockeries to him are basically a reflection of the mockeries he made towards her family.
He started with a pfft, and burst into laugher, she finished the beatdown with a more elegant glances into a mocking pfft.
He made a sarcastic praise, so did she.
He mocked her family rank (Knight) as a bunch of musclebrain idiots, she mock him being a baron's son with no inheritance right trying to asskiss his way up the ladder.
He questioned if they can survive being this stupid, she questioned if he's too stupid to do his job of teaching.