My little brother, my pet! Fifth part.

In the veterinary course, all students were allowed to take their pets to clinical classes. The idea was to be able to undergo treatments and exams and learn and train to deal with different types of mammals. My classmates from the student residence already knew my bizarre younger brother, and practically all of my classmates were already used to Charlie naked and on all fours, whether in our house or at our parties.

Thus, only the clinical professor showed some strangeness to the unprecedented situation. But it wasn't difficult for him to recognize that it was a beautiful didactic opportunity to show all students the similarities and differences between human organs and those of other mammals. We just had to sign a series of existing documents and forms for people who volunteered for experiments and clinical and laboratory tests. Charlie was already of legal age, and my parents also signed the endowment and agreement authorizations.

Each group of students worked with an animal on the bench; my group comprised my closest friends and a few female friends. With time and practice, I can say that none of us had any trouble or difficulty doing all sorts of experiments and procedures with our didactic material. It didn't complain or feel embarrassed even because we saw that the fag accepted that this was his role. It was evident that many times the pain and the fact that he was being oppressed in public turned him on; his cock was often hard and spurting.

We did several experiments with him. We inject vast amounts of hormones, adrenaline, and a wide range of drugs, to test the effects and reactions. We try its resistance to pain, burns, hunger, cold, heat, and electrical shock.

Several times we opened his scrotum and pulled his balls out to see if he could still cum, and it did a lot! While other groups anesthetized their animals for work, we muzzled them. He moaned like an animal when the pain was the strongest, but he coped well with everything we did.

When no professor was present at the clinic, we were even more sadistic. Some friends of mine were sadists, and they took particular pleasure in seeing him in a lot of pain. However, I can say that it was with them that I learned that Charlie felt joy and horny with all the suffering and humiliation they caused.

The bitch was indeed a slut masochistic!