Autofellatio

Autofellatio is an act of masturbation where a man sucks or licks his own penis.
Only men who have enough flexibility, penis size or both can perform autofellatio. Autofellatio is a niche in pornography. In some animals, like the Cape ground squirrel, scientists have seen these animals doing autofellatio and also manual masturbation.
According to historians, autofellatio in Ancient Egypt had a religious meaning.