Is it really "Unexpectedly Evil" when you take in account her personality back when she was human? For those who don't know, Jeanne's personality back then could be described as taking her personality when she's an Advenger and make her religious. I know there's a article at the "Fate/Grand Order" reddit Called "So I Found This..." that says this, so you could look it up there if you confermation.
And so, master was given a mysterious potion which reverted him to his child formWell then, master,Uh, I think I'll pass for now...SO STRONG!?What a terrifying woman...Come to your Onee-Chan.I remember...Onee-Chan will spoil you a lot, ok?