Lucretia

Lucretia, although slightly bigger than Lucius, is seen as less intimidating by her clanmates. She has more self-control than Lucius, but this does not mean she is any less sadistic. Her tactics are cruel, and her eyes without mercy.
She never forgets a dragon's wrongdoing, and makes sure they pay for it eventually, usually using her brother to execute the punishment. He does not question her requests, as he enjoys his playtime when she isn't attempting to interrupt.
Although she can fend for herself easily, she prefers to let her brother take care of pressing matters, as he has claimed her as the one thing he must protect above all. She has not yet found her destined place/item/dragon, but she honestly couldn't care less. With nothing to truly protect, she has no weaknesses, therefore nothing can exploit her.
Secretly, when the nights are cold, and the winds howl mournfully, she dreams of her parents, of the need for compassion, understanding and love. She dreams of what it would be like to lose her brother, the only thing she has left. She is particularly vicious the morning after, and stands a little closer to her sibling than usual, which says a lot, considering they act like they are conjoined at the hip.
She has shared this with Lucius many times, and he often comforts her by sleeping next to her the following night, only leaving after her breaths are deep and her eyes are sealed tight. No one sees him come or go, sneaking stealthily back to his own den to rest.
He doesn't tell her that he gets the same dreams.