Boxer: Widely regarded as a very playful and restless dog breed. They love to play all the time and always need a companion who will spent most of the time with them. It will be a great choice if you want an average sized dog. Now coming to the point, boxers possess a great relationship with cats. Most of the time they are seen to play and wrestle with the cats. But no need to worry they will never hurt your cat and you can be sure about that. This breed can be trained very well and can be used as guard dogs.