If it was me, I wouldn't have been able to concentrate in class after being involved in this situation. All I would be able to think about would be my dog tearing another animal apart and trying to get that animal some help so it wouldn't suffer. If John really was able to concentrate, then that DOES make him heartless.
But I believe John was trying to think his way out of the situation, and going to class gave him time and a good excuse (in his mind) to do that. John made a bad decision buying a dangerous, violent breed of dog. He made a bad decision to go to class, allowing Lucy to suffer and die in agony in the back of his jeep. And he's making another bad decision trying to get his animals back.
One bad decision after another. John needs to grow up, acknowledge his wrong, stop trying to get his dogs back, and make amends to the owner for the loss of her pet. It's the right thing to do.
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