I had a cat back in my college days that I rescued from a group home in the neighborhood. The mom was kind of feral, and when she delivered kittens, the director of the group home put up some flyers, offering up the kittens, otherwise, due to liability reasons, they were headed off to the pound. I grabbed one; an orange and white male.
I was in a class one warm California spring day, and there was a raunchy odor emanating from beneath my desk (no, it was not the infamous pants cannon). As the classroom got warmer, the odor became stronger.
A couple of days later, I was getting ready to go to class, when I came out of my bedroom and found "Rusty" marking my backpack. He was at the low cost spay and neuter clinic three days later. Don't think he ever forgave me for that...