Some days, it really sucks to be a person. Days when all the bills come at once. Days when the delivery to the bar is all of the wrong things and none of the right ones. Days when Terry is doing worse than bad and Lafayette won't pick up his phone. Days when Jane Bodehouse's son refuses to come pick her up. Days when every fucking thing that can go wrong does, and to top it all off there are vampires in his goddamn bar.
Luckily for Sam Merlotte, when it sucks too much to be a person, he has the option to not be one for a few hours. Collies don't have to worry about bills or boxes or drunks or vampires. Collies mostly worry about chasing rabbits ans squirrels and other small, quick wildlife, and getting their tummies rubbed.
Also luckily for Sam, there are plenty of rabbits between the bar and Sookie Stackhouse's home, and Sookie never shuts him out. She knows it's him and she still lets him in, pets him and plays tug-of-war with him with an old piece of rope, lets him up into her bedroom, even. She doesn't change for bed in front of him any more, which is a pity because he's pretty sure that's the only way he's ever going to get to see her naked... but that's another thing collies don't have to worry about: carrying a torch for a woman who'll never love you back.
Sookie won't call him Sam when he's a dog, even though she's fully aware that there's a person she knows behind those sad puppy eyes. He doesn't mind, really. Whatever helps her meet his eyes ten hours after scratching him into leg-twitching ecstasies. If calling him Dean helps give her the distance she needs, that's okay by him.
He doesn't know if she can read his mind while he's shifted. Maybe she just has preternaturally good instincts for scratching him. She always gets that tricky spot behind his left ear, and she digs both hands into his belly fur when he rolls onto his back. He gets petted a lot-- he does make a cute dog-- but nobody pets him the way Sookie does.
Once in a while, just to mix things up, he comes by as a cat. Sookie's a sucker for strays. He's pretty sure she doesn't know about this, but he's still not certain about her reading his shifted mind. Maybe she does know and just doesn't make a big deal about it.
Being petted as a cat is totally different from being petted as a dog. The finger action is completely different, and the ideal zones for scratching shift to under the chin and just in front of the tail. Plus, as a cat sometimes Sookie will pick him up and cuddle him, and that's pretty much the highlight of any week.
Sam knows better than to overstay his welcome. He always leaves before Sookie goes to bed, making his way back home with a considerably lighter heart. This is a damn sight cheaper than therapy he couldn't afford anyways, and he likes to think it does them both some good-- after all, spending time with an affectionate animal has proven health benefits. It's not as good as providing the barmaids with health insurance, but it's the best he can do.