You got Rin

Rin has messy blue-black hair and he is the son of Satan and has a twin brother Yukio. His hair sweeps down onto his eyes somewhat, has pale skin and intense blue eyes. When Rin becomes a demon-like, he gains two blue flame-like horns that floats above his head, long elf-like ears and slitlike red pupils while his irises remain deep blue. He has a tail aswell.

/Author/ I think having a tail is cute!

/Rin/ -laughs-

Rin has a protective and supportive personality, yet he can be very violent and tends to get into fights. He always supports his friends, tries to encourage and help them aswell. Rin can be clueless at times, such as saying phrases wrong. Rin might be immature aswell.

Although for being immature and that he gets into fights, he's protective as said above. That's what would make him to protect you from a danger, or even death.