Whenever Derek came home to his apartment and Meredith was not there, the place felt much too empty. He rarely got to experience that feeling, however, since it seemed that Meredith was always there. It was not that he minded. She was always willing to talk if he wanted, or let him sleep otherwise. He grew to expect the accumulation of Meredith's school things on his table, and the clothes that she left in various places around his apartment.

He let her keep the key he had given her when she stayed with her, and he did not realize exactly how frequently she used it until he got off at four one day, and saw Meredith sitting at the table leaning over a book as soon as he opened the door. She jumped when he came over and put his hands on her shoulders.

"Hey," he said. "What are you doing here so early?"

Meredith blushed. "I…um…usually come here after school. You don't mind do you?"

"No. Not at all," he replied, going to the refrigerator to pull out a soda.

"For the record, it's weird here without you. It's just… better than my house."

"Meredith, you don't need to explain. I gave you a key so that you could come in when I'm not here. I mean, I'm never here."

Meredith shrugged; then tossed her pencil on top of the book. "I've had enough of this," she sighed. "Why I need to know what happened in seventeenth century Europe, I have no idea." She stood and walked over to Derek, straddling him. He quickly put his soda on the table and put his arms around her back. She smiled mischievously at him, and then caught his lips with hers.

"Mmm, you should be doing homework," Derek admonished, running his hands over her sweatshirt.

"I should," Meredith agreed, trailing her lips down his neck. "I consider this you helping me with my homework."

"I am a very good homework-helper," Derek agreed. Meredith did not answer, just shifted on top of him, rubbing herself between his legs. In retaliation, he moved his hands up under her sweatshirt, and was surprised not to find a t-shirt under it.

He gave Meredith a questioning look, and she smiled as she ran a finger over the stubble on his cheek. "Didn't want to wear my school shirt anymore," she explained.

"Smart girl," Derek murmured, running his hands higher. "Maybe you don't need to do homework after all."

"Oh, I definitely do. But not now," Meredith said with a smile. "Now I don't want to wear this either." Before he could do anything, she had pulled off the sweatshirt. Derek found himself face-to-face with her pert breasts, contained in a lacy white bra. Hesitantly, looking up at her to check if it was okay, he put his lips to her left breast. She let out an appreciative breath and put her hands in his hair.

Derek was not aware when Meredith started messing with his belt buckle until she had undone it and was working on the button of his jeans. "Meredith," he grunted, lifting his lips off of her skin.

"Don't stop," she chided. Her fingers deftly popped open the button, and her hand brushed against his erection, making him groan. "Feels good, huh?" she asked deviously.

"Yes," admitted. "But Meredith, we can't."

She drew back, her hands still resting on the zipper of his fly, meeting his gaze. "But you're my boyfriend. Don't you want to…? Or not with me?"

Derek sighed in frustration. "Meredith, it's not that. Trust me, it's not that. Look, I made the decision….no. I let myself do what I wanted in… in dating you, but… until you're eighteen…"

Meredith's jaw dropped. "Seriously? You'll kiss me, take me out, buy me booze, but you won't have sex with me? How the hell did you come up with that line? Should I get you a pen so you can make me a list of exactly what we can and can't do?" As she gave this speech, she stood up, and grabbed her sweatshirt off the floor, pulling it back over her head.

"Meredith."

"I think I'll go home and play dolls. Or maybe blocks. That's what a kid's supposed to do right? Since I'm a kid?"

"Meredith."

"I'm mature enough for you to date; you say I don't seem seventeen to you. So what exactly do I seem?" She started slamming books closed and piling them into her backpack.

"Meredith."

"What? What, Derek?"

Derek opened his mouth, but then closed it. He did not know what, exactly, to say to calm her down. She stared at him as he floundered, and then shook her head and it stormed out of the room, the door slamming behind her.

Derek sat, staring after her. He understood why she was upset. He was upset. The problem was, he could not get it out of his head that he would be having sex with a minor. It was legal, he knew, she was over sixteen. But she was still a minor That would not bother him, in her case, except for who Meredith's mother was. No matter what happened, he knew that Meredith would never speak out against him. If Ellis Grey found out though… he had seen news shows about angry parents who had nineteen-year-olds imprisoned for dating their seventeen-year-old girls. A twenty-six-year-old would not be acceptable in anyone's mind.

Eventually, he got up and went to the bathroom to change into more comfortable clothes. When he walked in there, he saw Meredith's school uniform shirt on the floor. The image of her breasts bared before him resurfaced in his mind, and he scowled at the mirror. This was definitely a complication that he didn't like.

Late that night, he sat on the couch, his phone extension in his hand. He was trying to decide if he should call Meredith or wait until she cooled off. She would cool off, he was pretty sure of that. The cynical part of him wondered if she would come back merely to get out of her house. In reality, he knew better.

At nearly midnight, Derek had just decided to go to bed, when he heard a key scraping in the lock. He looked up to see Meredith standing in the doorway. She closed the door and leaned against it, looking at him nervously. One foot rubbed her leg. She was wearing pajama pants and a sweatshirt, but had her sneakers on.

"Hey," she said, and then bit her lip, a nervous habit he was getting used to and found endearing.

"Hey," he replied. She stood there, silently looking at him for several moments, with her arms crossed, and he realized that she had no idea what to do. "I assume you snuck out?"

She shrugged. "Mom got called in. She'll be home in a few hours but… you're not mad?"

"You're probably the one who should be mad."

"But… you're not? I mean… I yelled at you. And I left."

"Yes. But you were upset," Derek explained quietly. "I get that. And you're here."

"Yeah," she agreed. "I'm here. So we just…we can just… keep going? Like normal?"

"That's pretty much how it works. I mean, I guess we should talk about it, but overall, yes."

Meredith nodded, and slowly began crossing the room. Derek shifted on the couch to make room for her, and this seemed to give her reassurance, because she moved more quickly and sat down. He put his arm around her and she leaned in.

"So," she said quietly. "I turn eighteen in three weeks."

Derek chuckled, and rubbed his hand up and down her shoulder. "It's okay," he murmured. "Sex is not the most important thing in life."

"Tell that to teenage guys."

"Well, to teenage guys it probably is. However, I have been told that to teenage girls it's not far behind."

Meredith was silent for a moment, and he looked down to see her staring at the muted TV, her left hand fumbling with her watchband.

"You okay?"

"Hmm? Yeah. Just thinking. I wouldn't know. The whole teenage girls and sex thing. Sorry."

"Don't be sorry! So you haven't--?"

Her shoulder shrugged underneath his hand. "There wasn't anyone I wanted to with. I mean, maybe Sam, but he never tried, at least not until after I met you, and then—then I just wanted you."

"Well, who wouldn't?" Derek replied, then sighed. "But thank you."

They sat in silence for several moments until Meredith said slowly, "I have done some things." She sat up, and he turned to her, to see a small, almost wicked smile playing around the edges of her lips. He put a finger to the corner and traced her smile. She turned her head a little and kissed his fingertip. "Can I show you?" she asked. She reached out and began unbuttoning his shirt. "I want to show you." She ran her hands over his exposed chest and he shivered. "In fact," she said thoughtfully. "If anyone asks, you can tell them I raped you."

Derek shook his head. "That's not funny. I'd never do that."

"Well, neither would I," she shot back. Then, she reached down, and before he realized exactly what she was doing she squeezed the bulge in his pants and he moaned. "But I would like to show you what I can do. Will you let me? Or do I have to convince you?"

He was surprised to hear her talk this way. This was confident, and there was not much of that in Meredith. "Is my arrogance rubbing off on you?" he asked.

She blushed, and ducked her head a little, her shyness returning. "Maybe," she admitted. "But I know what I'm doing."

"Meredith," he said, his throat dry, as he leaned in to kiss her neck. "Don't tell me that. I don't want to think of any one else with you but me."

Meredith nodded. "Okay," she said, huskily. "I'm all yours." Then she began to unbutton his fly for the second time that day. Slowly, she inched them down, then slid off the couch, kneeling in front of him. She kissed his chest, running her hands over it. A voice in his head, one that sounded suspiciously like his father's, told him that he should not let her do this. He was probably sexually perverting her somehow. But she initiated it. She had, as much as he hated to think about it, done it before with other guys, and he knew for a fact that those guys could not have loved her as much as he did.

Then his thoughts shifted to Meredith's hands, which were toying with the waistband of his boxers. She ran her fingernails over the cotton and looked up at him, smiling. "Does that feel good?" she asked.

"Yeah."

"Do you want me to keep going?"

"Yes. If you want."

She shook her head. "This is about you, Derek. I want to please you. It'll make me happy to please you." She paused. "Please don't read anything perverted into that."

"I hate psych," he murmured.

She smiled, and ran her nails over his briefs again, causing his breath to catch. "Okay then," she murmured. Her fingers began to slide up his boxers to the waistband again, slowly, achingly slowly inching them off. When he was exposed before her, her eyes grew wide. "You're big," she commented.

"That's what they tell me."

"Hey," she said, leaning back. "This is not the time to allude to other girls." In protest, she squeezed his erection and he groaned.

"Sorry."

"That's better."

Slowly, Meredith ran her hand along his shaft, then faster. After a few minutes, she placed her lips against the inside of his thigh, licking slowly. She trailed her tongue up until it reached the hilt of his cock then slid it down.

"Mer," he moaned.

"Do you like it?

"God, yes."

"Good," she said, leaning back on her heels. "Time to take it up a notch." Her mouth went around his cock and she slid it up and down the shaft, and the sensation was almost overwhelming. Meredith may have been small, but she took him in all the way, sucking and licking in places that he did not know could feel so good.

Eventually, he choked out, "Mer, I'm gonna cum." She looked up, her eyes meeting his, and continued thrusting his penis down her throat. "Mer, I'm serious." Her gaze did not break from his, and he came, his cum shooting down her throat.

She slid back, staring up at him, and he watched as she swallowed. "You taste good," she murmured. "Was that okay?"

Derek held out his hand to her and pulled her up onto the couch. "It was great. You have no idea how much I want to return the favor."

"You could," Meredith said, smiling. "I mean, I wouldn't object." Derek sighed. Before he could speak she broke in. "I know. Don't worry."

Derek nodded, and then went to the bathroom to clean up. When he went back into the living room, Meredith was on the couch, her shoes and sweatshirt on the floor and the blanket around her.

Derek sat next to her and she tossed the blanket over both of them. He put his arm around her again, toying with the strap of her tank top.

"I should go home," she murmured into his shirt.

"Did your mother get called into surgery?"

"Mmhmm," she murmured.

"She'll be there a while. Stay here."

"Okay," she agreed, nestling against him.

Derek gently ran his hands up and down her arm and soon he heard her snoring. He grinned to himself. It always amazed him that someone so little could emit those sounds. He leaned down and kissed her on the top of the head. She reached her hand up and rested it on his chest. Her legs were curled around him, and he liked her warmth against him. She clung to him like he was all he had. Knowing that that was true was somewhat overwhelming, but with Meredith it did not matter.

Even with Meredith's snores, Derek dozed off without meaning too. When he awoke a pale blue cast had taken over the room. He blinked, rubbing his eyes, and almost forgetting about Meredith's small body against him. When he remembered, he swore. "Mer," he said, shaking her gently. "Mer, wake up. We fell asleep; you need to go."

"Hmm?" Meredith murmured, her eyes blinking open. "What's going on?"

"It's four AM. You need to go home."

"Crap!" Meredith jumped up, and almost fell, since she was tangled up in the blanket. Derek grabbed her arm, steadying her.

"Careful. Here, wait just a second and I'll drive you home."

"But—you have a shift. You should sleep."

"At six. I should go anyway. I can pre-round," he called as he ran to pull on clothes. When he went back into the living room, Meredith stood leaning against the wall, her arms crossed. She looked as if she were still asleep. Derek looked at her, then put his arms around her waist, putting her over his shoulder and carrying her out into the hall.

Meredith burst into laughter, pounding on his back, but he did not put her down until they were outside of the apartment building.

"Do me a favor? Don't fall asleep and fall off."

Meredith flinched. "Thanks. I really needed that thought." She scowled.

"Morning person, aren't you?" Derek mounted, and Meredith swung up behind him her arms clinging to his waist.

They sped to her house, and Derek parked at the end of the block. Meredith squinted up the street. "Good, Mom's not home. She always parks in front." She climbed off the motorcycle and leaned up to kiss him. "Bye. I'll see you later."

"Have a good day," he said. "Oh and Mer?" she turned, walking backwards. "I love you."

The surprised smile that spread across her face would keep him going, as exhausted as he was, for the twenty-four hour shift he had ahead.

A/N so that would be the 'M' rating. They're so cute and awkward our Derek and Meredith are