The Enemy of my Enemy is my Friend

AN: Hi this is a Reupload. It has been pointed out to me on a few occasions by a few different lovely people that the formatting needed work. This fic was a flawed little precious child for me. Only through rushing and my own laziness. Hope this is an improvement. No major changes just a tidy up.

Thank you so much to everyone that has read this story. I never imagined so many people would. It will focus on a ZeroxOC romance but Kaname, Yuki and the night class will also be featured. This will be rated M you have been warned. This is a slightly AU story and is set around the halfway mark of season 1. I have also read the mangas but my story deviates quite a bit from those especially later volumes. In this universe Yuki is fully human and she found out Zero was a vampire on her own. Zero has never bitten Yuki. Everything else should be pretty canon. Please read and follow and comment thanks. This chapter I'm listening to Troye Sivan – Wild.

Chapter 1 – Two blue hearts locked in our wrong minds.

Zero retched over the sink his dewy skin was cold and clammy to the touch. His long pale fingers trembled on the edge of the sink as he watched the undigested blood tablet swirl down the drain. It had been his third attempt today. It was getting worse.

The attacks, the thirst, the hunger pangs were becoming unbearable. At first he'd ignored them. He didn't want to admit what was happening to him but the urges were becoming too strong now. He needed…blood. The thought of hot, thick blood gushing onto his dry tongue and down his burning parched throat made him shiver but not in disgust. He shook his head roughly fretting a shaking hand through his silvery hair. He was disgusting. He glanced at his reflection in the mirror and shuddered. He was a monster.

His eyes were red with bloodlust his fangs chewed on his bruised bottom lip. He had become the thing he despised most. A vampire. A savage beast in human skin. He loathed himself. He was weak and filthy. He wanted to die to be free from the constant hunger that could never be sated. He placed a shaking hand over his bloody rose. It could end the pain. He brought it to his temple and closed his eyes. He didn't want to see what he was in that moment. In his final moments he just wanted to be free from the constraints of his own body. He squeezed the trigger. He heard rushing footsteps and felt small hands desperately trying to overpower him.

"Zero! Stop!"

Her voice was anguished. He heard the gun clatter into the sink from his limp fingers. He felt her gentle hands on his face and the rapid beating of his traitorous heart in his chest. He opened his eyes to see Yuki's big, beautiful brown eyes filled with tears her breaths coming sharp and fast. She was an angel. And he was a demon.

"Why did you do that?! I swore I would never give up on you Zero. We'll find a way. Don't give up on yourself!" She shouted defiantly a frown on her brow.

Her small hands slipped from his face to his chest where she balled them into fists and smacked them as hard as she could against his chest. She was so innocent, so cheerful. Even now. How could she do it?

"Yuki. I'm losing myself more often. I'm becoming level-"

"Don't say it!" She blurted out.

He almost smiled at her then. She was denying even what she could see right in her front of her because she believed in him. It almost made him happy. But then it made him feel sick. Yuki deserved happiness, someone whole, not him. No matter how much he loved her he would never allow himself to taint her. She was so pure. She brushed her mahogany hair aside revealing her pale milky throat. Zero's throat burned and the bloodlust coursed through his veins. She smelled so good like scented soap and vanilla and she was baring her throat to him. She was offering herself to him with a complete lack of fear or disgust. Oh how he wanted to bring his lips to her beautiful neck and bit. But once he did he would never forgive himself. He had to push her away. He had to push everyone away. It was safer that way.

"Yuki no. S-stop." He said weakly his throat rasping as he pushed her away.

"Why Zero? I want to help you, let me help." She said softly as she advanced closer.

He shoved himself against the tiled wall clutching his throat as his vison blurred around the edges. He was so thirsty and her blood smelled so good. His control was slipping.

"By giving me your blood? I-I won't do it Yuki. Now get out of here. Now!"

She gazed at him her eyes shining with unshed tears as he slid down the wall weakly. Yuki stood defiantly above him her hands flickering at her side.

"Don't come near me. Get out!"

He rasped as he felt the beast within him take over. Yuki hesitated but then ran. Her doe eyes had been wide with fear. That was the first time he'd ever seen her fear him. He smiled sadly. Good. Fear me. Zero lay on the floor his consciousness slipping away from him. Good Yuki keep running. And don't ever look back.

Rei yawned down at the contents of her book. Class was almost over. Good. She could see the sky lightening to blue already. Dawn wasn't far away. Kaname and Ichijo scribbled at either side of her as their teacher drawled on. He was pretty cool actually but as if she'd be allowed to admit to them that she found their vampire hunter teacher cool. They already thought she was weird.

She'd transferred halfway through the term and was still settling in. But she didn't think she'd ever fit in here. Here was no different from anywhere else. Kaname had taken her under his wing in the way an annoying overprotective brother would. He was kind but she needed just a little more freedom. She was the youngest here so everyone treated her like a baby a little but no one as badly as Kaname. Maybe he pitied her. He was a sucker for saving damsels in distress that was why he was so in love with Yuki. She'd figured that much out already. But Rei wasn't a damsel and she wasn't in distress.

Her keen hazel eyes roved over the rest of the night class. Ichijo was sweet but everyone else sort of scared her still. The impossibly beautiful Ruka just kept glancing at her as if she wanted to kill her. She knew she was jealous. It's not as if she'd asked Kaname to pay attention to her she didn't want it Ruka was welcome to him. Not that it'd do her much good he only had eyes for Yuki. Aido too she could feel his icy glare on the back of her head. They were all a little in love with Kaname. Personally she couldn't see it. She'd exchanged pleasantries with the others but not much else. She could add Cross academy to the never-ending list of places she didn't belong. She didn't feel like an aristocrat. She never had and never would. There had been a time when the loneliness had been bearable. One person made her feel almost normal. But that person was gone. And they weren't coming back.

Her sister Minako had been aristocratic enough for the both of them. Her parents had always urged her towards the aristocrat life, good education, good pureblood or aristocrat husband and she was all too eager to please them. They had been so different in every way in looks and in personality. In all respects they shouldn't have been close but they were sisters and that bond could never be broken.

She'd had the most beautiful long blonde gently curling hair and blue eyes the colour of the sea. She was tall and demure and elegant. The perfect Aristocrat's daughter. She smiled remembering how much she'd hated it when she'd call her Mini. They had been so different but she missed her so much. She swallowed the lump in her throat. Don't cry Rei she's gone now.

So her parents had shipped her off hoping the change in scenery would help transform her into an aristocratic lady. Not likely she thought. She was always getting into scrapes her hair was a dishevelled, wild mop of black curls just beginning to curl over her ears. Her mother would approve she hated it when she cut her hair she said it wasn't ladylike. She hated long hair it just got in the way she loved going on adventures and exploring. Her pale skin would be covered head to toe in cuts and bruises if it weren't for her vampire healing. She was short for a vampire made to look shorter by the impossibly long limbed night class that surrounded her. She knew she was a disappointment to her parents and she'd tried to be more ladylike especially after everything that happened with Mini but it was so hard to act like an aristocrat. She just wanted to run into the forest and never look back. Marrying into the aristocracy wasn't high on her list right now if ever much to her parents chagrin. She wanted to see the world first. All of it. She gazed out of the window daydreaming. Some day she would be free of here. Some day.

Zero hadn't been able to sleep all night. He kept seeing Yuki's wide eyes and his own red irises that had gazed out from the mirror. He shuddered. He didn't know who or what he was anymore. He patrolled the perimeter of Cross Academy. His duties as a Guardian helped him feel a little more human and right now he needed to feel that more than anything. Zero also needed some fresh air and time away from Yuki. He didn't know how much longer he could control the thirst. He exhaled angrily as the night class approached to go towards the Moon Dorm.

At least he wasn't here he couldn't have faced him, not tonight. Aido glared at him. Zero almost smiled at that. He hated him for disrespecting his precious Kaname. Good.

"So when will you joining us Kiryu?" Asked Aido teasingly.

Zero's blood boiled in his veins. Never. Kaname had already spoken to Master Cross about the transfer but he didn't want to think about it. Not yet.

Rei rolled her eyes why couldn't everyone just get along?

"Aido stop being a dick and leave him alone." Said Rei drawing him a tired look.

Aido blushed and his mouth fell open. She heard Ichijo try to contain a snicker behind his hand.

"Well we definitely need to teach this one some manners." Said Ruka scathingly.

Rei made to retort but she bit her tongue. She happened to glance at Zero who was giving her a strange look at that moment. Her face felt uncommonly warm as she looked at him. He was different from the others. Kaname had told her about him. It made her smile that Lord Kaname was jealous of this rakish guy with his untucked uniform and ear piercings all because he and his precious Yuki had a special bond. She noticed that his eyes were the most beautiful shade of lavender and his hair was white as snow. He didn't look like the others either. She shivered as she glimpsed the hunter's seal on his neck. He was just one big walking contradiction and she liked that.

Zero gazed at the nigh class with guarded eyes. He had noticed the new night academy student she seemed different from the others. She wore her tie loose and her sleeves rolled up. Her hair was tousled and she always looked like she'd just been caught doing something she shouldn't. She wasn't as stuck up as the others and seemed to find this whole thing terribly boring. Why was she sticking up for him anyway?

"Come on let's get to our dorms." Said Ichijo bowing at Zero respectfully. He didn't return the courtesy.

"Maybe we should take Kiryu with us give him a little guided tour?" Said Aido.

Shiki and the others laughed. She didn't. It wasn't funny. She couldn't imagine what he was going through.

Zero's face hardened and he pulled out bloody rose from his pocket and cocked it. Rei gasped. One shot would be enough to kill her…or him. She thought strangely. Aido and Zero glared at each other as Aido's ice crystals began to form beneath Zero's feet. She desperately looked around for help. Everyone except Ichijo was grinning enjoying the show. Weren't they going to help stop them?

"Do something." She whispered nudging Ichijo in the ribs desperately.

Ichijo gazed at her helplessly. Rei exhaled angrily. If you wanted something done right you had to do it yourself. She leapt between them.

"Leave it Hanabusa." She said firmly pushing him back gently ignoring the fact Zero's gun was inches from her head. Aido glared at her.

"Who do you think you are to challenge me? What are you doing sticking up for him anyway? Got a little crush on the soon to be level E have we?" Said Aido angrily a cruel smirk twisted on his angelic features.

Rei blushed at his words but hardened her resolve. How could he say that to him? She didn't know Zero or Aido that well but that just seemed unnecessarily harsh. Poor guy. Level E was her idea of a living nightmare. It was a living nightmare for Zero. Before she could retort Zero had pushed her aside his gun advancing towards Aido's temple. Her eyes widened. No! Shit where was Kaname when you needed him? She had to stop them.

"Whoa! Everybody timeout!" She shouted in a rush waving her hands over the night class.

She exhaled shakily her heart racing in her chest as Zero frowned in confusion. They were all frozen exactly as they had been except herself and Zero. He glanced at her then that unreadable expression in his eyes.

Zero had no idea what had just happened but it irked him that he found it difficult to drop his gaze from her hers.

He turned from her. She got the feeling he didn't say much. He was prickly all right but if she were Zero she knew she would be too.

"Hey wait up!" She shouted catching up to him.

He continued looking straight ahead barely noticing her presence.

"Won't they wonder where you've gone?" He asked his voice rough.

She grinned.

"Nope they can chill there till I get back."

Zero raised his eyebrows.

"You mean they're still frozen and you're just going to leave them there?" He asked.

She laughed at his expression. He thought she was crazy too.

"Yeah only I can unfreeze them. I used to play pranks on my family all the time. Don't worry they need time to cool off." She said her voice deep with nostalgia.

"Um thanks I guess." He said softly still not really looking at her.

She smiled. She got the feeling Zero wasn't the type of guy to say sorry or thanks a lot.

"You're welcome." She said quietly.

"Shouldn't you be getting back to your dorm?" He asked.

She shrugged. "Yeah I guess. I'm Rei by the way." She said halting her walk and extending her hand to him.

He hesitated and frowned down at her hand.

"I don't have cooties you know." She said with a grin.

She shook her head and withdrew her hand when she saw he wasn't going to take it. He must really hate vampires. She didn't blame him.

"O...k. Goodnight Zero." She was about to leave but thn she saw him clutch is throat.

His violet eyes reddened and he grasped her shoulders. She stayed perfectly still. He was thirsty.

"You don't have to be afraid of the thirst you know. Don't deny yourself." She said.

Her eyes never left his. She saw the lavender flickering beneath the red and he pushed her away roughly sinking to the floor his head in his hands. She felt immense pity for him in that moment but he wouldn't want her pity he didn't want anyone's pity.

"Go." He said roughly his voice rough and desperate.

Why was he being so stubborn? Rei didn't move a muscle. Zero tried to regain control but it was so hard. Her blood smelled so good. He usually didn't like the way vampires smelled but this one was different. Her scent was earthy and lightly floral like the woods in spring. It didn't cloy sickeningly sweet in her throat. She smelled good, maybe even better than Yuki.

"No. I won't. You can't scare me. You're thirsty. And my guess is the blood tablets aren't working and you're too stubborn to seek help from anyone because you don't want to admit what you really are. So you'd rather starve. Am I right?" She asked shakily. She didn't know why she was being so bold with a complete stranger. She felt strange.

He looked at her his fangs bared. A shiver ran through her body at the sight. There was something about watching him taken over by blood lust that made her stomach knot oddly. Zero's resolve was fading. Who did this vamp think she was she didn't know anything, but she guessed right about you didn't she Zero? Guess you aren't fooling anyone anymore.

"Did she offer herself to you? Yuki?" She asked her eyes never leaving his.

He stood and grabbed her roughly by the shoulders.

"Don't you EVER talk about her."

Rei swallowed thickly as she gazed up at him. He was fierce but she wasn't afraid of him. She watched the pulse point beneath his tattoo beating rapidly she could smell his blood just beneath the surface. It smelled good. She'd always heard anything below level C blood tasted disgusting but she doubted that. Her throat was dry and parched she hadn't noticed until now. She was due a blood tablet. She had never tasted real blood on her tongue and had never wanted to know how it tasted. Until now. Zero watched as her hazel eyes flashed red and her fangs protruded over her plump lips. She was thirsty too. They were disgusting creatures.

"Too honourable to bite her were you? Bite me instead." She said thrusting her wrist in front of his face the pulse point beating erratically.

Zero felt anger course through him how dare she so assume so much about him and correctly at that. Then he felt the anger be replaced by want. He could see the blood pulsing through her veins beneath the pale skin at her wrists. She smelled so good.

"S-stop why are you doing this?"

"Because you need help but you don't want to hurt anyone. I'm not her. I'm one of them. You hate me already so you have nothing to feel guilty about. Use me, hate me, and do whatever you want I don't care just drink. No one deserves to starve."

He shook his head.

"No." He replied shakily.

She pressed her wrist to his lips her heart racing. She'd never been bitten before. She felt his warm lips spread over her wrist and the sharp fangs scratching lightly over her pulse point.

"Wait. Not here. He'll smell it. I know a place."

She took him by the wrist racing into the forest. She ducked beneath low branches glancing behind to check on Zero every so often. They came to a clearing with some boulders and a little stream gurgling by. She came here to think sometimes. She'd never encountered anyone on her times here before. Plus the streams and the damp earthy smells of the forest might mask the smell. She pulled him down beside her on a large boulder. It was cold beneath her bare legs. He watched her hesitantly.

"Do it." She said firmly.

Zero took her wrist in his hand and without a moment's hesitation he bit down into the flesh firmly. He must be starving she thought. One of his hands was bending back her fingers roughly the other gripped her forearm. His grip would have left marks if she'd been human. She watched him drink greedily a strange feeling bubbling in her stomach. It hadn't hurt as much as she'd thought. It felt sort of good in a way. His fangs throbbed against the open wounds but it was more of a deep burning ache than a sharp pain.

He looked younger with his eyes closed and his hair across his face like that. She didn't know why she did it but she brushed his hair back from his forehead with her free hand. His hair was silky soft to the touch and shone silver in the dying moonlight. He was very beautiful.

Zero let her sweet blood flow down his throat. It tasted so good. In that moment he didn't care about anything else only the taste of her and how good it felt to drink her blood. She tasted even better than she smelled. She felt her fingers touch his hair gently and he thought of other fingers that had brushed through his every night when the nightmares got bad. Yuki. He froze pushing her wrist away. He felt better than he had in months. He felt satisfied and strong but how long would this feeling last?

"What's wrong? Have you had enough?" She asked softly.

He turned to her then. Her cheeks were flushed and she was wrapping her tie from her neck around her wrist. The blood would already be clotting but she couldn't let anyone see any sign of it. He nodded unable to speak. He felt disgusting. He wiped the blood from his mouth.

"Are you ok?"

Her eyes widened in surprise.

"Yeah. Are you?" She asked smiling as his eyes returned to lavender. He nodded.

"Why did you do that? Why do you care? Why not let me starve. The rest of them would have."

Rei didn't know the answer to any of those questions. Part of her felt an affinity with him he didn't fit in in his world either. She shrugged.

"I'm not sure. I guess I'm not like the others. I don't really fit in here."

He nodded. She wasn't like the others. But she was still a vampire. The sun was starting to come up. She had to go she had to unfreeze the night class and come up with some excuse to feed Kaname.

"I better go. Hey, Zero. Meet me here tomorrow before class ok? This can be our secret. No one has to know."

He frowned across at her.

"Why?"

"We'll make this a regular thing. I'm not a pureblood so my blood will only stop the blood lust for a while."

"What are you getting out of this?"

Rei deliberated for a moment then smiled.

"Knowing that I'm doing something that would make Kaname and my parents go crazy. "She said with a smile.

Zero frowned at her. She was a strange girl but hey anyone that wanted to piss of Kaname was fine in his book.

She ran off glancing back quickly.

"Tomorrow then." She said with a smile.

He watched her melt into the darkness swift and silent. She was crazy. He found a tentative smile touching his lips as he sat in the early dawn light feeling more clear headed than he had in months. He wasn't willing to admit it was because of her blood. Not yet. He could still taste her on his lips. He still felt guilty about what he'd done and he wasn't comfortable with this arrangement but if it protected Yuki then…maybe this could work.