Cock in a muzzle cumming twice

I put his cock and balls in muzzle , attached a rope to the muzzle so have his cock like on the leash. His cock and balls are totally at my mercy, I can pull the rope and make his cock do a funny swinging, splapping him hard on my hand and a lot of other great things but he is a lousy cheater and he start shooting his load and deprieve me of all the fun. I tried to ruin his orgasm but it looks like It was too late, his cock softened a little and he isn't so cooperative now so I have to keep him hard and put some hard work to make him to cum again.