In Hindu mythology, Prajapati is the master of created beings. Now: let me stop right here, and say that Hindu mythology is a complex thing, with several layers of religious texts written in different periods and locations, often conflicting (not that this is any different than most religions). I don’t personally have the confident grip on it that I do with other cultural mythologies, but hey: I’m workin’ on it.
Back to ol’ Prajapati. In the Hindu epic, the Mahabharata, he is the protector of the sexual organ (not the worst job).
He produces a number of children including a daughter, Ushas (“dawn”) who he then attempts to do a lil’ incest on/with. Now, when Ushas sees Prajapati coming at her in a lustful rage, she transforms herself into a deer and hauls ass out of there. Prajapati, to match her speed, turns himself into a stag, and catches up to do the deed. The offspring they have, predictably, is a baby deer. This cycle repeated itself not once, not twice, but 200-bajillion times; every time Prajapati got the urge, Ushas would pick a different female form and run, and Praj’ would pick the corresponding male form, catch her, and make a baby in said form. In this fashion, Prajapati and Ushas gave rise to all living creatures, including man.
Another myth tells how Prajapati rose, weeping, from the primordial waters. His tears that fell to the water became the earth, whereas those that the god wiped away became the sky and air. Prajapati then created the night and day, the seasons, death, and people to relieve his loneliness. This story conflicts with other Hindu stories, such as the creation by Brahma. The name Prajapati, however, sometimes refers to a variety of gods, including Indra, Shiva, Garuda, Vishnu, Krishna, and Brahma. Brahma, specifically, is often attributed with myths that later became associated with Prajapati. Whether or not it’s viewed as a title for the master of sex organs/the creator or a specific deity’s name depends on which text you’re looking at.