@Hour Page 10 the word "embarrassing" is misspelled. Very interesting so far especially the twist of her menacing glare is attuned to her being the demon lord in her past life. It seems like the previous demon lord was male based on comments but either way I look forward to this. Thanks for the chapter.
This has two options, she really is an incarnation of the demon lord or its a ploy for them to make friends.
My guess, taking account the air of the manga, the elements we've seen, and then extrapolating it, I would say that its all a ploy to get her into the friendship market