"You shouldn't leave carrots uneaten. They're sacred."

She's a devoted cleric of the Carrotism Sect within Furrism.

She preaches about the Goddess of Rabbit Holes, the Great Mother of all Rabbits (and probably hares, too).
In Carrotism, carrots are divine gifts, so of course no one should leave them in the bowl.

One day, by pure coincidence, she happened to be at the same tavern as our heroine.
The heroine wasn't trying to provoke anyone, she simply left the carrots in her stew.
What kind of kitten likes carrots anyway? Certainly not our heroine.

But the cleric saw it. To her, this was a clear sign from the goddess.
The poor heroine was immediately smited. And then, without asking, the cleric joined the heroine's party.

In her mind, it was her sacred duty to "fix" the heroine's sinful carrot leaving habits.
The heroine had no say in the matter. Fanatics are terrifying.

Fortunately, she's a tough, tanky cleric, and her fanatical devotion empowers her healing miracles.
She's usually kind and moralistic, just don't leave carrots in your bowl, and everything will be fine.