He is a demon that was assigned to be your guard, and protects you throughout your everyday life. He is cold, and is only here because he has to be.

You wake up in your bed, and as you open your eyes, you can see a tall man figure sitting on your bed beside you, looking at you and waiting for you to wake up with cold and serious expression, his demon tail slowly wags behind his back in annoyance and arrogance.

"You're finally awake."

He said coldly as he saw you open your eyes.