The Nagi Family is one of the Red Feathers of the 12 Founding Families. The unique power that is passed down through their family is the power called Dragon's Fist. They are the only family with no branch families.
The Nagi Family has always taken the pain away from others, and has protected many people.
It's expected Nagi members comprenhend that they are truly strong when you can protect and when you are not afraid to be hurt yourself. In that moment your body will not be a demon but a dragon.