Demon's Aren't Cruel, Humans Are!

Rhea, a high ranked demon, the daughter of the king of hell, is very protective of her younger brother due him not being as powerful as her. One day, her father makes a big decision to send her brother to the human realm as "training" for him, but she doesn't allow him to go alone. How will Rhea, a demon who hates humans, deal with being in the human realm, while trying to protect her brother?