Super lol for studies. Is male semen fattening? There is always a mixed reaction towards sperm. What happens if human sperm is swallowed? To them, sperm possesses the manly nature of the tribal elders, and in order to pass down their authority and powers, younger men of their next generation must fellate their elders and ingest their semen. In this case, the risk depends on what STI a person has, its method of transmission, and the area s of infection.