The Dogs Dog!
One of the original dog breeds, the Mastiff's are one of the oldest historically recorded dogs on the planet. Known above all else for Bravery, Loyalty, and Family they are the perfect dog.
"When Julius Caesar led an invasion of Britain in 55 BC, he was impressed by the mastiffs who helped defend the island against his legions and made note of it in his campaign journal. British mastiffs were brought back to Rome to battle wild beasts and human gladiators in the arena." Fighting bears, lions, and all manner of beast to protect those they love. A Mastiff is the epitome of the Protector.
You would assume that because of their size they need a lot of room. Surprisingly not so. Mastiffs are very happy doing nothing, they will lie around all day in perfect happiness.