When I was in high school we got a kitten from the biology teacher. Of course we had to give part of him back to her. Mom asked the vet if he did a vasectomy or castrated male cats. He said he castrated. She said, "Fine, I want his testicles." The vet turned red, looked at the floor and said, "You're kidding." Mom, who had, heretofore, thought it perfectly reasonable of the bio teacher to want a set of cat testicles explained the situation.
I gift wrapped the jar, with a bow, and gave them to her with a card from the cat.