The state of anticipating or expecting sexual intercourse from a social encounter, be it a date, a party, or a booty call
. It describes a period of optimistic waiting that is just shy of a sure thing
A: Girl, you gonna give him some?
B: I don't know, but he's sexpecting.
On the ride home from that date, the sexpectation was killing me!
Just because you sexpect something doesn't mean you're getting it.