Honestly this is when I realized this wasn’t just a good anime, this had the potential to be an all timer.
Also the scene that elevated both Paul and Rudeus into my S tier list for characters
Maybe this was not clear for anime-only so let me add some little-extra context:
Eris Unga Bunga monkey brain.
Eris think Rudeus is Genius Amazing OMG knows everything.
Orsted made her realize, Rudeus always protecting everyone, and she is always causing problems not helping him.
She loves the roles.
Swordsman attacks and defends
Magician protects and covers.
She wants that.
She wants to be the one protecting, so she feels that distancing like this is the best way for HER to grow, otherwise she will forever be kept under Rudeus wings being forever protected without giving anything back.
And Then she thinks, since Rudeus is so GENIUS AMAZING OMG, if she leave a napkin written some ungabunga dirt, he will understand, and he will do fine by himself, because he was the one protecting everyone (not Ruijerd, of course not lol).
Episode 21 and 23 of Season 1 gives some brief explanations of this
I will add the pages from the novel here that shows more or less this part of her thinking. The chapter where she reflects about her feelings towards all of this is bigger, but well this is the end of it.
Hope it helps =D.