Bone Throne
A place for a female to sit that comprises a man's lap and, specifically, his erect manhood. Use of this phrase usually implies that more than just sitting (namely, boning) is underway.
Alex's sister is hot! I may have to let her sit on the Bone Throne.
Throne Bone
When one ejaculates, the Penis goes that little bit bigger! Thats a Throne Bone!
As I penetrated that gal last night, I got huge "Throne Bone" when I came!
dirty throne bone
Having sex on the toilet when one of the participants is pooping.
Before I shower I like to have a dirty throne bone