colon tag
A game played by five or more sexually active adults in which one person "tags" another by inserting their sex organ or sex toy into another's rectum and shouts "Tag! You're it!"
Charles and Tiffany were getting it on. They thought they would mix it up a bit and try anal. Midway through, Charles shouted "Tag! You're It!" Therefore, Tiffany now followed Michael, who followed Jim, who followed Rita as "it" in colon tag.