Stavanger Bay where the watermelons grow

As though it hadn't been enough to bite Julep's ass in the morning, the little devil she'd been paired with at birth decided to do it again for some reason. Julep shrieked in pain as she jumped away from her brother, but at the moment she turned around to face him her face had become rage and her eyes lit with fiery hell. Julep simply did not comprehend why Isengrim had to be such an annoying little bitch, but she'd been sent to this pitiful existence to contain the monster that was her brother. She knew that much at least, that her purpose in life was to terrorize the boy's very existence. Proof of it was that she'd been armed with fangs and deadly claws of her own, and both were aimed at her instigator in a not so surprisive attack that was meant to subdue the little prick.

should I be concerned that I consider Julep a mature character so soon?