Disclaimer: See Chapter 1

How It Started

Actually, it all started with Metallica.

It was late at night, after another Al Pacino movie, when Mark made Addison listen to his iPod.

Well, he didn't make her. He just offered to be polite, and she took it to be closer to him. For once, short headphone cords didn't make her cringe.

He carefully unwrapped the headphones, and handed her the tiny music player, saying, "You can choose the song."

It took her less than three seconds to scroll through his entire playlist. "Mark!" She sat up quickly to show him, as if he didn't already know, and in the process, yanked the earpice out of his ear, "You have less than 100 songs!" She didn't even recognize most of the song titles.

"I just got it!" He defended.

She laughed and scrolled through his artist list, "TWO artists?!" She held it up, and mockingly flipped between her two options. "Hmm...I wounder what I should choose- Metallica or Journey?"

"I should have warned you." He grabbed the iPod and stuffed it shamefully into the pocket of his sweatshirt. "I knew you wouldn't like it."

"I didn't say that." She crossed her arms. "You never let me listen to it. How would I know if I like it or not?"

"Forget it." He looked away, leaning back on the couch. "It's not your kind of music."

She couldn't have him thinking like that. She wanted to have more in common with him. "Come on, that's sexist. Let me listen to it."

"Okay." He reluctantly let her listen again. "Here."

For the next hour they listened to Metallica and read medical journals on the couch. Addison could feel every movement that he made- when he shifted closer to her, when he turned the page. It was easy for them to be together silently. Every once in a while, Journey played and Addison would take a break, singing and dancing. Mark didn't sing, but he twirled her around as best as he could.

After every song, Mark asked her her she liked it. At first, she lied, telling him that she liked every song. It was such a girlish move, pretending to be interested in something so he would like her, but it just came naturally to her. She liked to surprise him, and he seemed to be so happy, showing her something new.

Of course, after her approval of ten Metallica songs, he figured it out and called her out on it. "You don't really like any of these, do you?"

She laughed, "It's not horrible."

He wasn't willing to forgive her so easily, and turned off the music. "You don't like it."

"Yes I do." Her breath came faster as she tried to cover her ground.

"Don't lie to me then."

She felt horrible, guilt sinking into her stomach. She wasn't supposed to feel like this, with all the complicated emotion. "I'm sorry. I really do like some of it. the music is nice. The vocals are just- kind of scream-y."

"Okay," He said, without conviction. He shifted over on the couch and then stood up, as if he couldn't stand to sit with her anymore. "Want to go to bed?"

"It's nine o'clock!" She couldn't believe that they were doing this. These past few weeks their friendship had been so simple; maybe they had it coming all along. "And you're mad at me."

"I'm tired." He left her in the living room and disappeared into the bedroom.

"Seriously?" She muttered to herself before dragging her feet into the bedroom.

He had stripped down to his boxers and another one of those white t-shirts that she loved.

"Don't run away." She placed her hand strategically on her hip, trying to seem like she had a little more control. He smiled slightly, making fun of the gesture, so she dropped her hand to her side. "Why are you so mad?"

"I'm not mad," he claimed and patted on the bed. "Come to bed."

"No." She remained still at the doorway. "We're friends and we promised each other that we would be honest."

"You weren't honest," he reminded her, climbing into bed and pulling the cover over himself. The sheets tucked just under his chin and she just wanted to snuggle next to him like always. He closed his eyes and turned over on his stomach. "Will you shut the lights off?"

She complied and tiptoed to the foot of the bed. "Mark?" She pressed her hands on his legs through the comforter. "Mark?" He didn't say anything or move. She crawled on top of him, enjoying the feeling of his heavy body under hers. He wasn't paying attention at all, until she mistakenly grabbed his thigh.

"Addison. Get off."

It was all too familiar.

He pulled her hand away from his leg and tilted his body slightly so she fell onto the other side of the bed. He kept her hand in his, though, holding it close to his chest. It wasn't particularly comfortable for her, sitting up, her hand buried underneath his chest. She lay down and it was a little better. "I think we need to talk about this."

"I'm sleeping." He turned, pressing his face into the pillow.

She rested her other hand on top of his back, and whispered into his ear, "I don't think I did anything wrong."

"Addison!" She watched his entire body tense and raise up. He looked at up with a pained expression and took a deep breath before he spoke, "I'm not going to do this. Maybe you and Derek talk about feelings and pretend to like each other, but I can't do that to you. I'm not your husband."

She sighed, not knowing what to say. She raised her hand and brushed the back of her fingers over his forehead. "All right." She slid off the bed and into the living room to collect her journals and clothes.

He immediately followed her. "Where are you going?"

"To find my husband." She stacked her medical journals neatly into a pile and slipped them into her briefcase.

He ran his fingers through his hair. "I guess I have to let you go then."

She glanced up at him for a moment and had to double take. His hair stuck out in all directions; his eyes squinted. He was actually tired. "Oh. Yeah." She put on her coat and slung the strap over her shoulder. "Thanks." She felt that they needed a stronger goodbye, like a hug or a kiss.

She gave a fleeting thought to appropriateness, murmuring, "See you tomorrow..." Her fingers grazed him somewhere on his torso as she headed out the door.

He caught the door before it shut. "Wait." He poked his head through the door. "Just stay." He tilted his head, trying to seem cute, but it banged against the door.

She smiled anyway.

"Stay. Come back."

She shook her head and left.

She didn't see him again for a week.

It was the welcoming dinner for the new interns, and she knew he would be there, which made her nervous. She didn't know if he would be mad or sad, or if he wanted to pretend like nothing had happened.

It would be awkward, and she absolutely dreaded going, much like every year since she became an attending.

At least Derek was required to go and she wouldn't have to pretend like Mark was her husband again.

She was looking forward to that part. Getting all dressed up, eating at a fancy dinner with her husband. Spending time with him. All the things she'd been missing lately.

Most of all, she wanted to make up with Mark, so they could talk and have fun again. They didn't exactly need to make up, though, because they didn't exactly have a fight.

But they hadn't spoken in days, and she could stop listening to Metallica.

"Bleeding Me" blasted through her earphones as she applied her make-up, waiting for Derek so they could leave for the dinner. She sat in front of the mirror in her bedroom, gazing at her reflection.

She thought she looked pretty enough to be presentable. Her hair was curled into a loose bun at the back of her head, and her flowing black dress curled around her calves. It was just low-cut enough to distract Derek, and hopefully hold his attention for more than four minutes.

She brushed a few stray wisps of hair back behind her ears, and Derek entered the room. She smiled at him though the mirror and turned down the music. "Ready to go?"

He came up behind her and rested a hand on her shoulder. They looked like one of those eighteenth century couples posing for an oil painting. He bent down and kissed her hair. "Yes. Let's go."

They took a cab, instead of taking their separate cars for once. She sat uncomfortably close for the first few minutes, until he gave in and wrapped his arm around her back. She turned her head all of a sudden to ask him a question, and her nose poked his cheek.

She laughed, "Sorry."

He took it as a cue to move away.

She looked down and tried not to pick at her fingernails. She attempted to ask her question again, "Have you seen Mark lately?"

"Yeah," It took Derek a moment to remember. "Oh- he asked about you. Did something happen?"

"What?" Oh, God. He knew. He could tell what Addison had been thinking.

"Did he say something inappropriate again? Addie- you're just going to have to get used to it. He's my best friend, and he's not going to go away anytime soon. You'd think after nine years..."

"He didn't say anything," she interrupted quickly. She prayed silently, thankful that he didn't know the truth. She couldn't imagine what Derek would think if he knew she'd been spending every Friday night with Mark. Maybe he wouldn't care about the movie-watching, but he'd throw a fit if he knew that she'd been sleeping in his bed.

"You guys can talk about it tonight. He'll be there."

She knew that already, but she wanted to talk to Derek. She predicted that he would get a page in the middle of dinner and then leave her with Mark again. She looked at him as he looked out the window. He'd never see her again.

She gave one last feeble attempt, "Do you like this dress?" She batted her eyes and modeled for him so he could see straight down her cleavage.

He smiled at her and kissed her cheek. "Yeah. You look pretty."

It was enough, though she had expected a bigger reaction. She was used to being disappointed, like he was used to seeing her in revealing dresses.

They arrived soon after, and she stepped out of the car first. Immediately, she searched for Mark. It was stupid; there was no one else on the street, but she still looked, hoping he'd be arriving at the same time as them.

Derek paid the driver and held out his arm to her. She took it, glad that they would look like a couple to the rest of the hospital.

They entered the reception hall and were instantly bombarded with compliments and conversation with colleagues. Loud music blared from speakers at the back of the room, drowning out most of their voices. A few brave (or lightweight) interns had managed to sway on the dance floor, pressed sweatily against each other.

"Is that how the kids are dancing these days?" Addison giggled at them.

Derek laughed along with her. "I guess so. It's embarrassing."

"Why don't we show them how it's done?" She tried to pull him towards the dance floor.

He yanked his hand away from her, glaring. "You know I don't dance."

She tried to play cute, sauntering back up to him, eyeing him seductively. "You dance at home..."

"I said no, Addie." He didn't seem to be that angry, but she didn't feel like having to work that hard to get her husband to dance. He pointed to the dining area, "Look. There's Mark. Go talk to him and save me a seat. I'll be over in a few minutes, after I talk to the chief."

"Okay." It was so familiar that it almost felt like deja-vu. Mark was watching her, a hopeful look in his eyes. Derek left her in the middle of the room, and she bit her lips and looked around. All of the twenty-some interns were eyeing Mark. Her Mark. Who was watching her. She strutted confidently over to him, making sure his eyes stayed on her.

"Hey gorgeous." He raised his eyebrows in an effort not to stare.

Suddenly, she felt much better. "Hi. You're not supposed to say that kind of stuff, remember?"

"I was just observing." He grabbed the glass of wine in front of him and took a sip. His eyes wandered around the room nervously.

"Thank you." She sat down in the seat next to him. "Why are you sitting alone?"

"I don't really like any of these people." He glanced with disgust at the mass of people crowded around the doorway, greeting newcomers.

Addison twisted her neck around to see a particularly ambitious woman with bleached-blonde flaunting a bit of thigh obviously displayed for Mark. She frowned, and turned back to him. "Everyone seems to like you. Especially all these women."

"Really?" Mark smiled arrogantly, and looked around, seeing the room in a new light.

She hit him in the shoulder, and he winced. "Ow. What was that for?"

"Nothing." It was selfish, but she wanted him to talk to her, not the slutty blonde woman.

"Are you jealous?" His jaw dropped in fake surprise and he laughed.

"A little." She blushed and felt her face heat up. It was awful, knowing that he could see her embarrassment.

"You know you're my favorite girl in the room." He wrapped an arm around her upper back and squeezed to reassure her. "You're the most...." He couldn't say it.

She stopped him before he tried again. "Thank you." She paused. "Just don't leave me here by myself. Please."

He seemed shocked at the degree of fear in her voice, but he lightened the tone of his voice to make her laugh. "I could never leave you." He gestured around the room. "None of these other women would watch Al Pacino movies with me. They wouldn't listen to Metallica with me."

"They would have sex with you." She stared at the edge of the table.

"Yeah, they would."

Addison rolled her eyes.

"But I would rather stay here with you, if you'll let me." He leaned forward, rested his elbows on the tables, and clasped his hands in front of his face.

She leaned forward to mirror him, her eyes shiny. "Mark..."

"Addison..." He scooted and moved his elbow to move closer. "I-"

She pressed a finger to his lips, and realized how soft they were. She traced his bottom lips with the tip of her finger, and lingered too long to be considered friendly. "Don't say it. Let's just think for a moment."

"Okay." They stared into each others' eyes for a few minutes before someone nearby cleared their throat.

Addison jumped in her seat. It was James Collins, one of the cardiology attendings. "Am I interrupting?" he asked.

"No," she answered. "Of course not."

"Actually, you are." Mark leaned back in his chair. "We were having a moment."

"We weren't," Addison told him.

"How are you, Dr. Sloan?" Collins asked him politely.

"Fine. How are you, Dr. Collins?" There was a certain exaggerated formality to his voice, and Addison did not appreciate it.

Collins shifted his feet, and bypassed the sarcastic response. "Excellent. And you, Addison?"

"I'm fantastic." She didn't mean to sound like she was making fun of him, but it came out that way.

"And ravishing," Mark added.

Addison blushed again. "Stop it, Mark."

"He's not lying." Collins adjusted his glasses, and admired her. "You look beautiful."

Addison did not like where this was going. She felt like she was back in the tenth grade, when she told Adam Walker that she wouldn't go to homecoming with him because she wanted to go with Kyle Cooper, who never asked her. "Thank you."

"Could I- um- have the pleasure-" Collins adjusted his glasses again. "-um- of a dance with you?"

Mark couldn't hold back a booming laugh. Addison simply stared at him for a minute, not knowing what to say. "I- I promised Derek the first dance. Do you know where he is?"

Collins gestured towards the mass of people. "He's busy, talking to the chief."

"Oh, well, I think I'll just wait here for him and I'll find you later, okay?" Addison tried to be as nice as possible.

It worked. Collins nodded happily. "Okay, Addison. I'll talk to you later."

He left Mark and Addison sitting at the table by themselves. Mark shook his head. "You aren't actually going to dance with him, are you?"

"I might." Addison looked into the crowd, trying to find Derek. "Derek won't dance with me."

"I'll dance with you," Mark offered. "The whole night."

"Okay." Addison grabbed his wine and finished it. "We need more drinks."

Mark pointed to the dancing interns. The number of inebriated guests had grown since Addison had first arrived. There were now more people on the dance floor, moving their bodies to the music. "You have to dance with me like that."

"Like that?" Addison raised her eyebrows incredulously. "What do you even call that?"

"Grinding," he replied. "It's very sexy and fun and you'll love it."

"It's not dancing!" she exclaimed in protest.

"Fine." He gave up. "Let's get a few more drinks in you." He left to get more drinks for them.

Someone tapped Addison on the shoulder. She whipped around.

It was the sultry blonde from before. "Excuse me?"

Addison grinned smuggly. She wasn't about to lose Mark to an intern now that she had him wrapped around her finger.

The blonde eyed Mark's empty seat. "I was just wondering- are you with the guy who was sitting there?"

Addison hesitated- it would be wrong to lie. Mark wasn't hers to claim. But she couldn't stand the thought of Mark with another woman, much less, another lonely night without him. She rested her arm along the back of his chair. "He's going home with me, if that's what you mean." It was catty and unprofessional, but she didn't care. It wasn't exactly professional that this woman wanted to get into her superior's pants.

"Is that a wedding ring?" The blonde crinkled her unblemished forehead in confusion.

Addison tried to hold back unkind thoughts as she covered her left hand with her other hand, feeling the rock dig into her palm. The woman was just trying to make Addison feel guilty about sitting with Mark.

Addison was just about to make up an excuse when Mark came up from behind her and sat down. "Meet a new friend?" he asked her, his amused expression revealing sexual connotations in the question. He handed her a glass of wine.

She turned towards him, stroked his chest lightly, and looked up at him with her best puppy dog eyes. "Mark. You're taking me home tonight, right?"

He paused for a moment, and looked at the blonde, taking in her shiny, curly bob and the curve of her hips. Addison, frightened out of her mind that he might actually say no, yanked on the collar of his shirt, bringing his eyes down to hers.

At this, she knew there was no contest. His eyes twinkled a bit, letting her know that he was only playing when it came to the blonde, and she relaxed.

He turned his head and squinted at the blonde, as if he were having a hard time deciding. "What's your name?"

"Gina." She held out her hand to him. "I'm a neurology intern."

Addison held her breath. Gina probably knew who Derek was, and maybe, who she was. Gina would be one of those interns who made her husband laugh during surgery, like Addison could on the off-chance they actually had a surgery together. But Gina would also inflate his ego, something Addison refused to do.

And it was just another reason that Derek would rather stay at the hospital than at home.

"You're Dr. Shepherd's wife?" Gina asked.

Apparently, Mark had mentioned something about Derek, and Addison had missed it. "Yes," she said uncertainly. "I am."

She pointed at Addison, her eyebrows raised in sudden realization. "I think I saw you! I watched one of his surgeries in med school, and you were in the observation room."

"I watch all of his surgeries." It came out a little harsher than Addison had intended, and afterwards she attempted to soften her expression so she didn't come off as a cold-hearted bitch.

"Oh. So you're just friends?" Gina gestured between Mark and Addison.

How the hell did they get back to talking about Mark and Addison? Gina was a conversational wizard, Addison decided. That must have been how she got through med school. She couldn't say anything, but just let a swig of wine swish down her throat.

Mark watched her and took a sip of his wine as well before answering, "Yes." He paused. "How about I talk to Derek? Get you in on a surgery?"

That was her Mark, his answer to tough situations was bribery. She took another sip of wine.

Mark continued his persuasive argument to get Gina to leave, "... and I promised him that I'd take Addison home tonight, but I'd love to go out some other time."

She already had the piece of paper in her hand, and she gave it to him. "Call me sometime."

He smiled and stuck the piece of paper in his pocket. "I will."

When Gina was out of sight, Addison made a gagging sound. She was glad that Mark hadn't bought into Gina's act (yet) and that she could still go home with him.

"Stop." He grabbed the bottom of her chair and pulled her closer. "You didn't actually think I would desert you, did you?"

"I don't know." She thought about how she could never give Mark everything he wanted, and how he looked at Gina. She needed to win him over, "I was hoping you'd stay." She just wanted him to lean in and kiss her.

He didn't, but he came awfully close. "You didn't stay when I asked you to."

Yes. She knew she was a hypocrite and she tried to justify it by claiming obligation to her husband. It was a weak argument, supporting the fact that Mark could leave her whenever he wanted.

But he was, in fact, more faithful than her.

She only had one option: apologize and explain. "I'm sorry. You wouldn't talk to me and I was scared."

He sighed, almost annoyed with her excuse. "But I was tired and it was such a stupid fight."

"Yeah." She supposed that made sense. Or maybe the alcohol was making her thought-process a little hazy.

"I talk about important stuff. If you do something to really piss me off, I'll tell you." He tilted his head forward, so their noses were almost bumping. It was her favorite place to be, as if she was so close that she could see inside his thoughts.

He continued, "I don't think that we should waste time arguing over stupid things when we could be enjoying each others' company."

She took a deep breath and stated, "That is very smart. Let's do that now."

He turned his head to look at her empty glass of wine. "How much did you drink Addison?"

She definitely wasn't drunk. Or tipsy. But maybe a little dizzy and silly. She always acted like a child after a few drinks. "Just that one. And the one before. And I had one at home," she counted and smiled. Home made her think of Derek. "Where's my husband?"

"I don't know." He looked around for Derek, but couldn't find him.

She placed her hands on his upper thighs and hoisted herself into his lap. It was crowded, in between the table, but she felt much safer. Mark was warm and nice to be around.

"This isn't good," he whispered. "You don't want to do this."

Yes, she did. "We're not doing anything," she claimed, perched on his knees. "When's dinner?" Her stomach had started to growl an hour ago.

He picked her up by the hips and placed her back into her own chair.

No. She wanted to be near him. She reached for him, and he grabbed her hands, clasping them near her shoulders. Her forehead fell forehead until it made contact with his, and she stared at him. "Mark. Derek's probably already left," she realized out loud.

"I'm here." Derek appeared out of nowhere and sat down in the chair on Addison's other side. "What the hell are you two doing?"

"Playing a game." Addison found that she was much better at lying when under the influence of alcohol. She let go of Mark's hands and turned her entire body towards Derek. "Where have you been?"

"Making small talk..." Derek stared at Addison as she smiled slyly and slid forward in her chair. She fell into Derek and kissed him.

Derek shoved her back in her chair. "Wow. You have had too much to drink. And you're horny. Mark, what did you do?"

Mark looked away in denial. "I didn't do anything."

"Were you at least watching her?" Derek wiped his mouth on a nearby napkin.

"I'm not a babysitter," Mark said as he handed her a glass of water and a few crackers from the baskets in the middle of the table. "If you weren't too busy brown-nosing the chief..."

Addison threw her napkin down on the table and stood up. "I can take care of myself!" She began a fast-paced walk to the hallway, afraid that if she went any slower, she'd lose her balance.

Mark caught her by the arm.

"Don't stop me!" She tried to push him away. "Especially when you treat me like a child in front of my husband. Can't you stand up for me for once?"

"Fine." He let her go. "But dinner is starting and I know you're hungry."

He was right. "Fine." She trudged back to the table with him, and proceeded not to speak for the rest of the meal, in fear of sounding drunk and annoying her husband.

A/N: Okay, so this is part 1. It was originally 1 whole chapter, but I like to update faster. The next part is better. This is all really just exposition.

So Spoiler for the next chapter: Addison is not really that lightweight.

You'll see. It's good. Kind of sad, but it works. And there's a lot more Maddison.

Okay. Reviews would be appreciated.