At the Northern Fort

At the Northern Fort summary:

Paw pads wrapped in white fur. Fluffiness around the neck. A bushy tail. A rounded figure that was the very definition of furball! ――――A certain j.a.panese girl had been reincarnated into such a fox cub; Milfiria.
Milfiria was told to watch the house by her mother, as the mother left for the capital. However, unable to bear with the loneliness and deciding to chase her mother to the capital, Milfiria became lost in a fort protected by strong knights.