Who gives Juvenal his name in "Juvenal Nyx"? How are their encounters described?

Juvenal Nyx is named by a woman who calls herself Julia and makes him a child of the night. She takes him to bed and when he wakes later, he finds himself chained to it. He hollers and screams to no avail. Finally, Julia returns, drops her robe and naked, walks over to him and bites his forearm. Suddenly, he wants to bleed for her, even more than having sex with her.