Warnings!!! - There are some small spoilers from season 2, episode 17, so don't read if you haven't watched that far. Also, there is light swearing and mentions of death and guns. Don't read if any of these things are triggers.

    Sam Winchester did not have good luck when it comes to women.

    Whenever he gets close to people, they die. His mother died when he was a baby, his girlfriend, Jessica, died after he went on a hunting trip with his brother, and his love interest, Madison, died after being infected with the werewolf curse. He just never thought he would be able to find real love in this world, not after everything he and his brother suffered through during their short lives.

    However, you were different.

    You were the first girlfriend that didn't make Sam worry. Growing up as a hunter yourself, you knew how to take care of yourself in supernatural situations. There was never any doubt; you had been hunting by yourself for most of your life, so the boys knew you could handle anything these monsters threw at you.

    Despite the certainty of your hunting skills, Sam and Dean were beginning to worry again.

    One night, there was a brutal murder in a small town after one of the brightest full moons in history. The body found was scratched and mauled, yet everything was there except for the heart. You knew exactly what you were looking for, especially after your run-in with Madison.

    After spending a few nights with you, though, the boys feared that the werewolf was much closer than they expected.

    You had been dodgy lately. Whenever the sun started going down, you always found an excuse to separate yourself from the group. Sam would offer to follow you, but you were never interested. You always wanted to be alone, which was weird for you. Now that you had solace in Sam, you never wanted to be away from him. It was strange for you to deny yourself of him for such long periods.

    When the boys woke up the next day, you were never there. You stayed out for entire nights, never once coming back to the motel room. When you finally did show up, your hair was always a wreck, a nest filled with stray leaves and broken twigs. The first night, the boys assumed you had been attacked, but when you reassured them that nothing happened and continued to show up disgruntled, they figured that something more sinister was going on.

    Then they found the scratches.

    One night, the boys put their foot down and forced you to stay with them. Sam refused to let you leave; he wanted to prove that his fears were stupid, but he couldn't do it if you were running around all night. Also, if you were being attacked when you went out, then you would be safer in the motel room with his arms wrapped around you anyway.

    The next morning, though, you weren't there. Sam slept so well now that he had you in his arms that he couldn't feel you sneaking away from him, but when he woke up, he knew that something was wrong.

    Sam and Dean swept the apartment for any trace of you, but all they found were jagged scratch marks on the windowsill. At first, the boys assumed that the werewolf had kidnapped you during its hunt the night before, but when they realized that the only destruction showed someone running out of the room, they began to doubt even that theory.

    Sam was devastated. He feared the future of your relationship; if you were a werewolf, he would have to kill you with a silver bullet, just like he did to Maddie. There was no other cure for the werewolf curse.

    He couldn't kill you too. He had already lost so much.

    There was only one way to be sure. They had to follow you.

    So, that night, when you made a cheesy excuse about needing a quick drink at a nearby bar, the boys let you go without a fight. You cringed as you watched them stare at the dingy television, paying you very little attention at all. Even Sam barely looked at you, making you feel awful.

    You knew that your secrecy and distance would take its toll on your relationship, but you didn't expect Sam to ignore your existence completely.

    But the boys were smarter than that. They gave you a two-minute head start before following you. They needed to know what you were doing once and for all.

    Sticking to the shadows, the boys followed you around the town. You took them to the craziest places, and it was then when the boys realized what you were doing: shaking off any stalkers. You made crazy random turns and circles in an attempt to lose any person that might be following you. As smart as you were, you weren't clever enough to lose the two hunters.

    Finally, you ended up in a circular clearing in the middle of the woods. Sam's heart was pounding at this point; all signs pointed to you being a werewolf. The longer they followed you, the more apparent it became that they would have to kill you soon. Tears welled in his eyes as he stumbled behind you. Dean tried to ignore it before he too broke down; he hated it when his baby brother hurt.

    You sighed as you kneeled in the middle of the grass, the light of the full moon casting its beams on you. You reveled in the energy that coursed through your veins, the feeling of freedom envigorating you for the night to come.

    In your relaxed state, the transformation began. Suddenly, the veins in your wrists began turning a dark purple-ish black color, the fluid filling them and rising further and further up your arms, your eyes glowing a bright yellow in the dark night.

    The boys couldn't wait any longer. It was time to act.

    Without warning, the boys jumped out of their hiding spots in the treeline, pointing guns and flashlights in your direction as they screamed at you. You were so surprised, jumping to your feet in an instant as you prepared to run. Unfortunately, the transformation was underway, and there was no stopping it now.

    "What the hell is going on?" Dean shouted, his eyes narrowing at you as he prepared for any possibility, "What are you?"

    You were reeling as you attempted to hold off the transformation for long enough to explain, gasping and gaping as you tried to keep it in.

    "(Y/N), what's going on?" Sam called, his voice softer and less accusatory that Dean's, "We can't help you if we don't know what's happening."

    "What are you talking about, Sam?!" Dean thundered, "We know what's going on. She's a werewolf, and there's nothing we can do about it!"

    His words pierced through your mind, frightening you as you watched Dean grip his gun tighter. You weren't a werewolf, not in the way they were imagining, and you needed them to keep you alive long enough to explain that.

    "It's not what it looks like! I'm not dangerous!" you gasped, your breath hard to come by as a slight sweat broke out on your forehead. It took an enormous toll on your body to stop your transformation, and you weren't sure you could hold out any longer.

    Dean merely scoffed. "You're crazy if you think we'll buy that. If it's not what it looks like, then what the hell is happening to you right now? What's with the purple veins and the yellow eyes, because that doesn't happen to normal people."

    Sam couldn't say anything more as he watched your nails grow slightly longer, ending in razor-sharp points. Your teeth filed similarly, producing shiny canines that looked like they could puncture through anything.

    He was devastated. How could he lose the woman he loved to the same horrid curse that stole his last interest? How could anyone be that unlucky? He couldn't stand to watch his brother point a gun at you any longer.

    You gaped at the heartbroken, lost look in Sam's eyes. You couldn't stand to see him hurt so much because of something you did, but you didn't have much choice. Your time had run out.

    "I can't hold it anymore!" you screamed before tensing in preparation. Sam and Dean both pointed their guns, their trigger fingers itching to release bullets.

    Thankfully, it never came to that. You jumped toward the hunters, turning into a beautiful gray wolf and shedding your clothing in the process. The boys had never seen someone turn into a full wolf before; usually, werewolves looked like a half-human half-wolf hybrid.

    What were you?

    You were grateful for their momentary confusion. Their hesitation gave you just long enough to run away into the woods, disappearing behind the clusters of large trees that separated you and the two troubled men.

    The boys groaned as they found themselves in a sticky situation. On the one hand, they knew they should go after you in case you tried to kill someone else tonight. However, on the other hand, they wanted to give you the benefit of the doubt. There was so much about you that didn't align with usual werewolf attributes, making them curious.

    Were you telling the truth?

    After sharing one look, both boys knew that they wouldn't be hunting you that night. They had too many questions, and killing you would stop them from getting any answers. They also knew, deep down, that neither of them would be able to kill you, not right on the spot if the situation required it.

    They returned to the motel room for a restless night, the two of them tossing and turning as they worried about what you could be doing out alone in your wolf form.
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    The next morning, you nervously approached the motel door. You knew you needed to face the boys after what happened the night before, but you weren't sure you could do it. You couldn't handle their piercing eyes and hateful stares.

    It felt like you lost control of your body as your fist knocked softly on the door, barely making a sound. However, in an instant, the door swung open, revealing a hurting Sam.

    "Get in here," he spoke, but his voice lost all authority. There was no trace of anger or fury; you could only see a sense of dread and disappointment as if Sam had already accepted how this would end.

    As you crossed the threshold, you noticed Dean standing behind the couch, his gun trained on you. You knew better than anyone that Dean was an unmerciful shot; he would only miss if he wanted.

    "That's close enough," Dean grumbled, his eyes never once looking away from you. You gulped as you noticed the unmistakable glint of the real silver bullet resting in the barrel.

    "Guys, just let me explain-" you began, but you couldn't finish.

    "Explain what?" Dean sneered, "Explain that you're the werewolf we've been looking for these last couple of days? Explain that you're the one that killed all those people and ripped out their hearts? Explain that you've lied to us for several months?"

    Dean's harsh words stung worse than you would like to admit, but you knew it wasn't his fault. He was scared and confused, worrying about having to kill his best friend and brother's girlfriend.

    "I deserve that," you nodded, biting your tongue to distract you from your hurt feelings, "but it's not what you think."

    "Then what is it?" Sam asked softly. He seemed physically and mentally defeated by the events of the last few hours.

    "I'm not a werewolf-" you began again.

    "Bullshit," Dean snapped, "We watched you turn into a wolf in the clearing. That is the definition of a werewolf."

    "Okay, yes, that's right, but I'm not a werewolf in the normal sense," you clarified, "I'm a wolfblood."

    "Wolfblood?" Sam questioned, his eyes crinkled in confusion.

    "Nice try, sweetheart, but there's no such thing as a wolfblood," Dean rolled his eyes, figuring that you were toying with the two hurting men.

    "No, really," you rushed, "A wolfblood is similar to a werewolf, but they have very noticeable differences."

    Dean opened his mouth to argue, but Sam put his hand up, effectively stopping his smart comment. "Let her talk."

    "Fine," Dean nodded, "You better start explaining before we have to kill you."

    You watched Sam flinch at the word "kill," but you had to move past it quickly. Dean was not known to bluff in these situations.

    "A wolfblood is a normal human who has literal wolf blood in their veins. If someone were to take my blood right now, it wouldn't be a human's blood; it would look like it came from a wolf. This allows us to transform into one whenever we want. We can control our transformations, unlike a werewolf. They just become harder to control when the moon is full, or we get angry," you explained, observing the boys' expressions carefully as you tried to read their emotions.

    "Say we believe you. How do we know that's any safer than a werewolf?" Dean asked, but you could tell he was faltering slightly, his grip relaxing on the gun.

    "Wolfbloods have total control of themselves when they transform and can remember everything from the transformation," you reassured him, "I remember last night. All I did was hunt a small fox for some dinner."

    "What, were humans not good enough?" Dean chuckled dryly, earning a glare from Sam.

    "I couldn't be the one killing people," you shrugged, ignoring his callous comment, "No one died last night. Werewolves feast on humans, and nothing can stop them when they desire food."

    "She's got a point," Sam spoke for the first time, "There's no way she could be the werewolf we're hunting."

    "Now, I did find something really helpful last night," you sighed, flashes of your hunt replaying through your mind, "I picked up a scent. It smelled kind of like a wolf, but not like anything I've ever smelled before. Maybe that's our person?"

    Sam and Dean shared a look, weighing their options. Both of them wanted to work something out with you, but they knew they couldn't risk other people's lives, including their own, to fulfill their own selfish desires.

    "How do we know for certain that you're safe?" Sam asked, his chocolate brown eyes trained on yours, a certain softness blurring around the edges.

    "You can watch me tonight," you suggested, "There's going to be another full moon. I'll stay here, and you guys can monitor me the entire night. If I do anything dangerous, then you can put me down immediately."

    The boys nodded simultaneously. It was as good an option as any.

    "Deal," Dean agreed before quickly putting his gun down and walking away. He couldn't stand to be in the middle of you and Sam for any longer.

    "I hope this works," Sam nodded, still keeping his distance from you. He couldn't allow himself to get any more attached until he knew for certain that he wouldn't have to kill you.

    "It will," you smiled, longing for the second you would be able to enjoy the closeness of Sam again like you did in the past.

    "Good," he smiled a small smile before following after his brother, leaving you to contemplate tonight's transformation.
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I have had this idea in my head ever since I watched the second season! I'm so glad I finally wrote it. I hope you guys enjoyed it as much as I did. Let me know if you guys want to see part two!