I strapped down a boy and injected his balls with his Covid vaccine and the other ball with his booster. Vaccination is required to be in our hospital so I was just following the requirements.

A little blood drop from each ball was the only sign and that was easily wiped away. He moaned for a while but I did not give him any pain medication. I let him savor the experience. It was important that he learn who was in charge. He can whine if he wants but no one will believe him.