Yes, I think there are human alien hybrids, if 'aliens' exist. I wouldn't call them aliens, though, as my personal belief is that they are originally from Earth. One theory is that they were an offshoot of our human ancestors who went from land mammals to an aquatic environment, lost their hair and evolved in a semi-aquatic environment. Their stay in the water explains not only their lack of hair and somewhat neotanous appearance, but their intelligence as well. Humans grew in intelligence when they returned to the water for a brief time, as did dolphins. Everything I've seen points to this theory, which means they are not angels or demons but simply closely related cousins to us. It seems dangerous to me to either glorify or demonize them. IF we are capable of reproducing with each other then there is little doubt in my mind that they are from Earth, not another planet let alone another star system, not to mention developing two arms and legs, nose, mouth, eyes, etc. on the other side of the galaxy. It seems more likely to me that they are closely related to humans genetically.