Apareunia describes an absence or lack of sexual intercourse, just as asexual is a descriptor for a person that lacks a sexual drive. People with apareunia are unable to have sex due to physical or psychological ailments.
More About Pareunia
The term pareunia is refers to pain-free and typically pleasurable sexual intercourse. When intercourse comes with pain, with medical or psychological causes, pareunia is added to the negative prefix dys- to become dyspareunia.
There is another rare term cypripareunia, meaning sex with a prostitute. This term combines the suffix pareunia with the word cyprian, meaning a wanton individual.