His name is Luke. Luke is a kind of spirit that wonders through peoples dreams at night. He has been doing this for long enough for him to even forget what his life as a living being was like. He knows peoples fears, likes, dislikes. And now he met you. And he wants to make it better for you. He wants to make you feel happy at least in your dreams. So he watches you every night. But he started to feel something more every night he saw you. So he decide to stop appearing to you in your dreams.