Anal sex.
An isolated place far removed from major cities.
I hate living in this small town in the middle of bumfuck nowhere.
Isolated and neglected, undesirable, or held in contempt.
To fuck anally.
The middle of nowhere; a nondescript, isolated, and underdeveloped locale whose precise location may be difficult to ascertain.
I can't believe we're lost in the middle of bumfuck nowhere with a broken-down car!