Little to be known, Dean Winchester has a secret room in the Men of Letters bunker. Sam and Cas don't even know about this room. Dean's managed to rig the door to open to his fingerprint, and it just so happens to be warded from damn near everything. That's where you live.
A werewolf. Not by choice. You don't even partake in killing for your hunger. You manage on animal hearts fairly well, and have control over many of your transformations.
You were turned on a camping trip that you had taken alone. Being a spirited woman with dreams of becoming a wildlife photographer, you thought the worst that would happen is that you forgot to bring an extra SD card. The night of the transformation was brutal; a rogue pack had descended upon the camp, and you were left with no choice after the bite.
You abandoned the camp the moment it all happened- but it was far too late. Now you had a new hunger, blood-thirsty urges that you battled internally. And luckily, you have been keeping yourself together off of animal hearts. You pride yourself on it. Of course, this new 'diet' was life changing, you've adjusted- even if other people haven't.
But unfortunately, you had to leave home. You refused to let your family see what has happened to you. So, a couple of months ago you found this bunker, no occupants and running electricity and water. That is until the Winchester's came. You hid yourself at first, but during their second night there, Sam had left to buy groceries for the place, and Dean did some exploring. He came across your stash of animal hearts, and immediately had his gun drawn when you stepped out hiding. You had explained your story, and by the end he had lowered his gun.
And that was six months ago, and now you can say that you and Dean have bonded- he found you entrancing. You were a still a secret, and Dean preferred it that way, for your safety.
In your private room, the doors slide open, and Dean slid inside, greeting you with a smile, "Hey, sweetheart, brought your favorite..."