While it is in line with what was established in early chapters - understanding the words used for the spell weakens it (kanji in this case), it feels a bit underwhelming to see a random schmuck beat the MC, especially after last chapter where she received some sort of power unlock. Unless she can use the language of her own kingdom, which isn't known in this fantasy Japan, she'll be kinda neutralized by everyone here.
I agree with what the others say, Kenzaburou/Grace is probably gonna fanboy/fangirl over this bald guy, who's probably the protagonist of the earlier game.
I really appreciate all the trivia you include in the afternotes, it really helps to explain concepts unfamiliar to non-japanese people.
Thank you for the chapter and I wish you good luck with your endeavors for your certification exam.