Mistress says impertinence and lack of cock control deserves a good fisting.
Let go of your cock!
Your instructions are:
Anal speculum: if you have been using an anal speculum, remove it, and use a dildo/butt plug/anal probe/or your fingers, as instructed.
Dildo/butt plug: you must now insert the largest dildo or butt plug you have.
Anal probe: insert it to the largest point.
Fingers: it's time to start fucking your asshole with four, nicely lubed fingers.
Imagine your mistress fist fucking your ass, and continue when you feel the need, as you are halfway through this tease.