1 definition by Teksune

Generally speaking, this is a term of endearment for a male, or female, who is the submissive in a dominant/submissive (hereby referred to as D/s) relationship. D/s relationships come in many different flavors, to include Master/Mistress and slave, though more common is the Owner/pet variant.

Specifically speaking, a Sexpet is usually referencing the pet, who's primary function is relief and enjoyment for the Owner/Mistress/Master through sex, foreplay, and other intimate interactions.

The pet usually sees his/herself as an animal, usually a domesticated housepet, but some see themselves as more varied creatures like a fox or even a leopard.
In addition, usually the pet is nearly dependent on the Dominant's initiative, as the sub tends to have no drive of his/her own.