1 definition by lsiusA

A person (male or female) that you used to date (but no longer do), but still will sleep with you now and again.
See also Imaginary
Ex: "Hey, I know we stopped dating because you're tremendously creepy, but I think we can at least be sex exes, don't you?"
Other person: (No response; tends not to talk to people he's imagining in his head)
by lsiusA August 13, 2011
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