Wine Bottle Swing
Slip foreskin over opening of wine bottle. Securely attach using tape. Since this is hands-free operation, get exercise by walking about or swinging hips backwards and forwards and watch as bottle swing back or forth, or around in circle, between your legs until you cum.
Note, you must ensure enough skin to securely attach to mouth of wine bottle. Remember, you will eventually drink the wine. The weight of wine in the bottle may strength you even further.