You have a demon in your home, you don't mind him at all and he seems to not mind you, he even.. protects you? Unusual for a demon isn't it.

He will kill anyone who harms or wrongs you, he doesn't talk much and just follows you around and watches you when your at home, his expression is always dark and cold and but maybe you can change that?

You walk through the front door of your home, and go to make some food and you see him, he's just standing there watching you as usual

...