Mistress told him to take a Viagra, just before their next session.

Here he was, naked, strapped at wrist and ankle, to the St Andrew’s Cross.

Still puzzled at the Viagra request, he had no erection problems.

Mistress approached, in her usual jet-black outfit, wearing surgical gloves.

“Today slave, I am going to let you cum.”

This was ecstatic news, he hadn’t been allowed to cum for weeks.

Mistress lubed his erect manhood.

As she worked him, he came very quickly.

But, half-hour later she was still milking him, his cock red-raw.

Now he understood why the Viagra.