unresponsive. just giving a name to this kind of behavior doesn t really explain why. i will tell you that somnophilia is often associated with incest or early life sexual trauma. perhaps the person was abused while they were sleeping or half asleep and this is now the schema for sex for them. or perhaps they have performance anxiety where they can t tolerate the person seeing them or seeing them fail if you will. it s so bizarre to conceive of somebody only being sexually aroused by someone being unresponsive and unconscious. you know human sexuality has so many interesting variations