Kings and Emperors in the ancient world (depending on their sexual orientation) had not only concubines but also catamites (male concubines), in addition to their many wives.
The word is also used to describe the practice in early Japan, where monks would have sexual relationships with younger monks; samurai with pages; and noblemen with younger members of the aristocracy.
The word catamite is derived from the Latin catamitus, itself borrowed from the Etruscan catmite, a corruption of the Greek Ganymedes, the boy who was seduced by Zeus and became his beloved and cup-bearer in Greek mythology.
It was the afternoon of my eighty-first birthday, and I was in bed with my catamite when Ali announced that the archbishop had come to see me.
In Cormac McCarthy's depiction of survival in a post-apocalyptic society in The Road, where many have reverted to cannibalism, the protagonists encounter, while hiding from a distance, people that were enslaved and who are referred to as "catamites," along with pregnant women and carriage-pulling slaves.