The man is tired of finding smelly "gifts" from his cat on the carpet. He installed a recognition camera, a smart plug, and a blender in the room. A script was written for the blender that starts an electrical appliance when a pet tries to sit on the carpet and do a dark deed.
The noise of the blender scares away the pet. If there are people in the room, then the program does not work and the appliance does not start.