Rusty rainbow
n. When a younger homosexual man is penetrated from both ends (e.g. spitroasted) by two considerably older gentlemen.
"Bruce and Peter sure gave Steve the ol' rusty rainbow Friday night at Cameron's Audrey Hepburn party. I heard they broke the handicapped toilet bar and were snorting crushed viagra off Steve's back!"
Rusty rainbow
When a male bends his own penis around and inserts it in his anus
Tim why don't you go give your self a rusty rainbow