Photo: Courtesy of Men's Health // Men and dog lying on grass(Men and dog lying on grass)

"Remember these rules," said my new housemate Adam about my other new housemate, Diablo, a wolf-German shepherd mix who looked as though he had eaten more jugular veins than Snausages. "Don't make quick moves, don't try to touch him, don't look him in the eye, and you'll probably be fine."

I was 6 months out of college and hauling my cheap belongings into a cheaper Salt Lake City bungalow. Adam, an Apache construction worker, explained that he'd rescued his dog from a sadistic drunkard who had beaten the animal half to death with a golf iron. Then Diablo growled as if I were the guy's caddy.

"Quiet," Adam told the beast, not unkindly. Diablo's growling ratcheted down, but only a notch. No wonder the rent was so cheap.

For the next 3 weeks, the growl never stopped. I almost got used to it, the way I almost got used to navigating the bungalow with my eyes trained on the ceiling. Every once in a while, Diablo sniffed my groin with his elongated snout, which could snap moose femurs like pretzel sticks. It was all I could do to keep from fainting.

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Our relationship changed one searing afternoon in August. Having come home early for lunch, I heard Diablo snarling at me from his fenced lair in the backyard. His growling carried its usual tone of hatred, but I sensed an additional chord, the barest tone of vulnerability in the heart of the largest carnivore I'd ever lived with.

As slowly and reassuringly as I could, I approached the fence. "It's okay, buddy," I said, trying to channel Saint Francis. "Easy, boy."

Diablo's problem was soon apparent: He'd upended his water dish in the 101° heat. What I decided to do next terrified me, but the alternative -- doing nothing -- seemed as cruel as beating the brute with a sand wedge. I unlocked the gate and slowly, slowly moved inside his territory. I could feel Diablo's breath on my leg, the guttural vibrations of his growl. Smoothly, slowly, I reached for the water dish, righted it, filled it from the wall spigot, and retreated. The growl was silenced by desperate, maybe even grateful, lapping from the dish.

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When I returned home at 6:30 that night, Adam was cooking his dinner, and Diablo was in his usual evening spot beside his master's La-Z-Boy. He was sitting on his haunches, watching me silently. The growl had stopped.

From that point on, our bond deepened.

If you've ever become best friends with a former bully, you know how gratifying it can be. With Diablo beside me, I felt invulnerable -- it was as if I'd developed a superpower. In the eons before modern weaponry, dogs like Diablo must have bestowed a sense of invincibility upon those fortunate human beings they trusted.

I got a delicious taste of this a month later, when I was jolted from a deep sleep by the sounds of Diablo in a rage. A couple of my ne'er-do-well friends had broken in at 3 a.m. to invite me out for drinks, which they had hoped I'd pay for. Diablo backed the slackers against a wall.

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I gave him an affectionate scratch behind his ears, which, of course, did nothing to calm him. "You know what they say about sleeping dogs, eh, fellas?"

After a quick recitation of Adam's list of "don'ts," I hugged Diablo around his neck and watched my friends slink off into the night. The last thing they heard in retreat was my voice switching to pupspeak.

"Who's a good boy, Diablo? Who's a good boy? You are! Oh, yes you are!"

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