Learning additional languages is a great thing to do. I am uncertain from which cognate in Latin--or loanword from elsewhere--the French "le butt plug" comes. (perhaps it is Quebecois?) However, the interplay of royalty is inspiring. Gold and purple have long been considered regal colours on account of both cost in construction or rarity. In this manner we are treated to the treatise that gold is permanent and purple wavers.
Consider kings and queen. They are adorned with a gold crown passed from generation to generation in perpetuity. Much in this fashion, the gold implement stays put. Their fashion--robes, capes, etc.--are all wavered on account of individual need. The purple object, similarly, is tasked with adjoining gold in consideration of this special and specific noble cause.