Chapter Ten: You Must Know That I'll Follow You

Meredith looked up slowly when she realized that Derek's eyes had been on her, solidly, for over a minute and a half. She dropped her breakfast back onto the plate.

"What?" she demanded.

"That's the third meal you've made out of that pizza," he observed. She glared at him.

"You're eating muesli. I can't believe I've known you my entire life and not known you were that guy."

He laughed.

"You're crabby today. Is something happening?" he asked curiously.

"Something happens everyday," she said, her tone somewhere between cynical and cheery.

They would have intercepted them, had be been the type to wake up at that hour. He passed by Meredith's car hours after they went in, passing by it without noticing.

He was tired. It had been difficult to explain to Addison, why he needed to go back to Seattle to make peace with Derek. She'd wanted to come with him, but she'd managed to convince her not to. He didn't fancy explaining that Derek wasn't the true reason for his stay.

She'd never really understood his and Derek's attachment to Meredith, and Mark wagered that she'd understand less when she knew he was going to visit her now that she was all grown up.

In theory, anyway. Mark didn't quite believe it yet.

He walked through the doors of Seattle Grace Hospital and stood awkwardly in the entrance. Richard Webber had been a father to him, Derek had been his brother, but he doubted that any of them would welcome him here.

He wondered if his betrayal of Derek would be the first thing that Meredith couldn't forgive of him.

"Excuse me?"

The intern he'd called out to stopped and glanced toward him, looking annoyed. He raised his eyebrows, surprised by his luck. Instead of looking underfed and pale in the fluorescent lights of the hospital, the girl he'd seen was tall, blonde and attractive.

"You looking for a patient, or to check yourself in?" she asked.

"A Doctor, actually. Do you know Meredith Grey?" he questioned.

"Oh, you know Meredith? Hi, I'm Izzie Stevens. We have the same resident," she explained. He put on his most charming Mark Sloan smile and shook her hand.

"So do you know where she...?"

A familiar voice stopped him.

"Mark?"

Izzie glanced at her watch in annoyance and realized that she had to leave before seeing the scene in its entirety. She walked toward the elevator as Meredith moved toward Mark.

As she waited for the elevator, she caught sight of Derek on the overhanging corridor and smirked. She knew the bare details of Mer's histories with them. This would be interesting.

Meredith felt herself lifted off the air, felt his strong arms on her back, encircling her waist, her chest pressed in to his. She felt her own arms move around his neck, her lips smile, a laugh escape them.

He set her back down on the ground, a smile still present on his face. She reached a hesitant hand to his cheek to touch the stubble present.

"Come here."

She followed compliantly, still dazed, when he pulled her toward a slightly more secluded corner, under the stairs. Both of them unaware of the eyes that had seen them.

"My God, Mark..."

He smiled down into her gray eyes, still the ones that had adored him as a child.

"I missed you, Mer."

She smiled.

"I can't believe you're here. Derek's going to be ecstatic. God, he didn't even recognize me when I ran into him..."

These words confirmed it: she had no idea. For some unknown reason, he'd kept it from her. He was still just Mark, he wasn't the enemy yet.

"This is so great. You have to come over tonight. Derek and I are living together, it's..." She continued to speak, but he couldn't quite hear her.

Derek and I are living together...

So it was always true, about Derek getting the girl. Her words brought up a surprising, almost forgotten jealousy in him.

"You're all grown up, Mer," he said in disbelief. She blushed.

"You know, you say that every time you see me," she pointed out. He shrugged.

"Well, each time it's just a little bit more true."

Years ago, if Meredith could have guessed that any of their relationships would have lasted, she would have said her own with Mark. She would have predicted nothing of what had happened. Not between Derek and Addison, not between Derek and herself.

"Maybe you've stayed away too-,"

He cut her off. Not like his words, in the playful banter way that she could have expected, but in a different way altogether.

His lips, even after she'd got over her surprise, were unlike any that she'd ever felt. His arms encircled her like they'd done just minutes before, like they'd done so many millions of times but he held her closely, he held her without fear.

And she kissed him back. Even though he was Mark, not Derek, and even though she had never loved him as much, even when she knew she should have loved him better.

Her arms didn't move around his neck. Her lips pressed up against his, she slowly opened them, he spoke her name softly, but her arms stayed her own.

So when more arms came, when he was ripped off of her, it was only her lips that required separation.

She heard the crack of bone against bone, saw the blood began to spurt, heard the yelling, but couldn't even begin to understand.

"What the hell is going on?"

Meredith jumped slightly. She'd seen her stepfather angry, plenty of times, but never before like this. Never so livid, never so likely to rip the head off of anyone who got in his way.

"Chief..."

It was clear that he hadn't really wanted an answer.

"We can't have people... punching each other and... making out with my daughter on my surgical floor!"

Mark winced and pinched the skin at the bridge of his nose. Here, apparently, was another person who didn't know the whole story.

"Richard..."

His eyes went to Meredith, but he didn't calm down. She took a deep breath and surged forward.

"I'm sorry about the kissing thing. Besides that, I have no idea of what's going on."

He glared at her for another moment before turning to face the two men, both sitting in their chairs, their arms crossed, facing away from each other.

"Would one of you care to explain why my Head of Neurosurgery felt the need to punch out his best friend on my OR floor?"demanded the Chief. Meredith looked curiously at them. She'd been startled, when she'd realized that the arms that had pulled Mark off of her had been Derek's. He still hadn't met her eyes.

"A few months ago..." the three of them looked toward Derek, who had spoken first. "I arrived home late last night. I walked upstairs to my room to find Addison, like I did every night. But I knew..."

He glanced at Meredith for the first time, who frowned, knowing that he was talking about but not knowing the why.

"Something was wrong. I stepped on a jacket. I knew what was wrong, and I knew exactly what was happening. I opened the door to my bedroom and what did I find, Mark?"

Meredith spun around to face Mark, slowly realizing in horror the meaning of it all.

"Addison and I. In bed together."

Derek's jaw tightened, but he said nothing. Mark looked down to avoid the look that Meredith gave him.

Richard sighed.

"Derek..." He looked up. "You put your weight behind that punch?"

Both of them glanced at the shiner on Mark's eye.

"Yes, Sir."

"So when you said you were living with Derek I didn't know you meant you were living with Derek," remarked Mark.

"Please. If we were together, do you really think I would have let you kiss me like that?"

"To be honest. I didn't think you'd let me kiss you at all," he replied flippantly.

"You know, I'm not even sure I'm speaking to you right now."

"Come on, this is way too much of a twist for you to ignore."

Meredith cleaned the wound on his face and smiled.

"Fine. How the hell did it happen?"

Mark shrugged and sent her his best innocent look.

"She was lonely, Mer. And I was... there," he explained lamely.

"She's your best friend's wife, Mark!" exclaimed Meredith indignantly.

"It's weird though. Didn't seem to bother him much."

"What do you mean? He just laid you out on the floor."

"When he saw me with you."

"What?"

"He saw me with Addison, literally in the throes, and he walks away. Then he sees me, just talking to you..."

"We were kissing, stupid," she said, rummaging in the drawer for supplies.

"He saw us before then."

Meredith rolled her eyes.

"God, you're such an ass. I miss older brother Mark," she lamented.

"However, he didn't seem to like the kissing that much."

He glanced back at Meredith, noticed with less denial than Derek had that she really was a woman now, in all senses of the word.

"I didn't mind the kissing so much."

She rolled her eyes and gave him a mirror to hold.

"What are you doing?" he demanded.

"You need stitches."

"I know. Give me the needle, you can hold the mirror."

She watched as he gave himself sutures.

"So what are you doing here, Mark? And you do know that I'm a Doctor now, right?"

"Well maybe I'm just here to make amends and make out with my favourite blonde intern. Speaking of which, I think I found my second favourite before. She's tall, name of Izzie?" Mark ended his speech with a smile.

"Sleep with Izzie and I'll lay you out on the OR floor. Are you going to New York? I need you to not be here when Derek and I sort all of this out," she requested.

"What, so you can join the Dirty Mistress' club?"

She glared at him.

"Derek's heartbroken. And one of my oldest friends. We're living together. Don't read into it," she ordered.

"You know, when you were younger you were never this mean," he complained.

"Well when we were younger you were my hero. And your thing with Addison was theoretical. Now it isn't."

Mark finished his suturing and took the mirror back from her, brushing his fingers against hers as he did so.

"Yeah. And so was your thing, with Derek."