If you're looking for a large, loving companion (with a little slobber involved!), you can't go wrong with an English mastiff. These massive dogs have been used as guardians for thousands of years, but they remain one of the sweetest breeds on the planet. English mastiffs don't require a lot of exercise either, but due to their large size, they are probably a better choice for owners with large backyards. Male dogs, for example, will measure over 30 inches at the shoulder and will weigh well over 100 pounds. The short coat is easy to maintain and is available in fawn, brindle, or apricot.