Your ass should be pretty loose by now.
Untie your balls give them some rest, also remove the clothepins for now.
You should be completely empty by now, just your naked body and nothing else.
Stand upright and hit your both ass cheeks as hard as you can.
Repeat this 25 times with 2 seconds in between each hit.
Do you feel it burn yet? You should, otherwise you didn't hit hard enough and will repeat the 25 hits until you feel the burn.
When you feel the burn mastrubate to an edge. NO CUMMING just an edge you don't want to make me mad already.