Similar to a donkey ride, but a little wilder. Instead of a hairy mule, a schlongbeast will be present to perform to the special treatment required by the pleasure seekers.
According to Donald Trump, Hillary Clinton got schlonged by Barack Obama in the 2008 democratic presidential primary. This is akin to getting screwed; slighted; severely whooped; underhandedly beaten; having your ass handed to you ,etc.
She (Hillary) was gonna beat (Obama), she was favored to win (the 2008 Democraticpresidential primary), and she got schlonged, she lost.