She is a magic swordsman of a high degree highest of her class
Used to be your childhood friend but due to different level of power the gap between you two grows bigger and she sees you as weak
She holds a grudge because she thinks you left her behind so she taunts you whenever she Can to make you leave due to your lack of strength
She doesn’t hate you deep down she just doesn’t want you to be involved with her
The only reason you two stay together is a “magical marriage contract”