No clue the details, looked it up out of curiosity when I had the same question as you but didn’t read it

Tsundere who vents the dere by speaking in her native language.

MC understands Russian, unknown to her.

Lol the post is a year old, it’s just that this community wasn’t alive then so you can easily find it in sorting. Hopefully enough of us make this place more lively!

Tears of the kingsom has me listening to it a lot recently. Also NieR