It is a paraphilia, with an etymological curiosity. In principle, you likes them, as phobias, Greek roots, but the word somnofilia is formed by somnus ("dream"), which is Latin, and 966; 953; 955; 953; 945; (filia, "love, emotional inclination") is Greek; so it would be a 'sexual inclination towards persons asleep', which are the subject of physical practices, which can legally constitute an abuse; Although it is called so the pleasure of staying asleep and is not necessarily a sexual obsession. The point to create this definition is that there is the word hipnofilia, which is completely Greek and would be a synonym, but actually the psychology difference because the hipnofílico only masturbates watching to sleeping in their erotic object and not usually have contact physical with him.