Eleanor's oath of allegiance was certainly not a spur-of-the-moment decision but instead the result of careful consideration.
It served as her formal response to that nightmare: if there really came a day when she had to choose between love and her ideals…
She would choose the former.
But no one knew this yet, so they all chuckled and called her "Knight Girl" (Ritter_Mädchen). Aske even joked, calling her "my Knight," causing Eleanor to be unsure whether to feel sad or happy.
Emotions subtly complex, she could only bury everything deep within her heart.
After resolving the sudden crisis of the grown-up Mia, the group continued on their journey. Along the way, Nora and Thira both took the opportunity to have a chat with Aske—although Aske declared his complete trust in them, given that Eleanor had already knelt to swear allegiance, they felt the need to show some form of commitment too.