A/N: I changed the title of this chapter. 'Jealousy' just seemed so lameeee.

D POV

Last week, Mark decided to give me a key to his house - lately I seem to be getting there when he isn't there, and, if Meredith isn't home, then I'm forced to sit in the driveway and wait. Given recent events…it might be awkward to throw pebbles at Meredith's window anyways.

I had been waiting half an hour in the kitchen, for Mark to show up, when he texted me, saying he had an unplanned basketball practice.

Great, just great.

I had stood up, preparing to lock-up and leave, when Meredith walked in with a guy on her arm. Now, don't get me wrong - I had told Meredith we could see other people…but I guess I just hadn't been expecting it so soon.

I sat back down; I wasn't about to leave and let this loser wreck what I was trying so hard to keep built-up. Two weeks. It had been two weeks since we had agreed we could see other people. Two weeks since Mark had scared the living shit out of me. Two weeks since I decided no matter how much he scared me, I still wanted Meredith, and then this loser was going to come in and ruin it all. The small smiles and 'accidental' brushes of my hand against her arm would mean even less if she was seeing someone.

Meredith finally saw me and jumped. I smiled smugly when I noticed her loosen her grip on...him...and bring her arm to her side. He looked up then, too, and I realized I had seen him around school - Alex Karev. He leaned over to whisper in her ear, and my eyes narrowed.

"Meredith...what the hell is Derek Shepherd doing in your kitchen?" I heard him ask.

"Ask me yourself. I'm right in front of you." I said with a hint of anger in my voice as I walked closer.

"Oh..uh of course. So..what are you doing here...?" he finally asked, looking around the room awkwardly.

"I'm a friend of Mers." I explained, smiling at him.

"He's my brother's friend." she told him as she glared at me. Karev just looked confused. Good.

Finally, Karev decided to go into the living room after Meredith told him she needed to talk to me and she'd be there in a minute.

"What do you think you're doing?" She whisper-shouted, smacking my chest a few times.

"I don't like him! There's no telling what he's going to try with you..." I responded, backing away and rubbing my pectoral.

"Nothing more than what you did!" her voice dropped a pitch. "Come grind with me!" She finished.

"Are you mocking me?" I asked, my eyes narrowed. "I was kidding!" I leaned in close "Not that I wouldn't like to." I whispered, running the tip of my nose up her cheek.

I backed up and smiled at my handiwork. Thoroughly flustered; just the way I liked her. Suddenly, Karevs voice broke through our bubble.

"Mer? You comin'?" he called.

"Yeah Mer, you comin'?" I mocked quietly. I smacked her butt lightly as she went up the stairs and when she spun to give me a death glare, I backed up with my hands raised.

"I swear, Derek!" She threatened.

"I'll be good! I swear" I responded, "and...ifImnotyoucanpunishme." I added quickly. She let out a frustrated sigh and I couldn't help but smirk.

M POV

Things were awkward to an extreme level. Sitting in my living room with Derek on my right and Alex in front of me.

"So...Karev-" Derek started.

"His name is Alex!" I hissed. He didn't even blink.

"So Karev. How'd you meet Mer?" he asked, looking at me from the corner of his eye.

"I uh...well...we're in biology class together and she asked me if I wanted to come over and study...study date...have one, I mean…" he stopped his explanation when Derek's eyes narrowed and I elbowed him in the ribs. I shot Alex an apologetic look. "Well not a date date I just umm...well. You're kind of protective of her aren't you?" he finally asked, looking slightly annoyed.

I groaned inwardly. I just knew Derek would say something...some kind of innuendo or something to try and tip Alex off and ruin my study date. It wasn't even a real date...it's just that being around Derek and liking him and not being able to do anything about it...it was frustrating. I needed someone I could talk to and tease and hug...I was beginning to think Karev-Alex- wasn't that person.

"You could say that. Just watching out for my girl, here" he punctuated his sentence by wrapping his arm around me and pulling me against him.

"Your girl?" I asked angrily as I squirmed out of his grasp. Resistance was futile. Derek underestimated himself sometimes, when he said he was weak. If this was any indicator...Derek Shepherd was anything but weak. He kept me pinned to his side without even faltering in his smile.

I couldn't help but relax into his grip when he casually stroked my arm with his index finger. Alex, being his oblivious self, hadn't noticed a thing other than the scarily protective junior staring him down. He probably thought the whole "grab Meredith and hold her against you" thing was nothing more than brother-to-sister love. If the last few weeks were anything, I'd say that Derek and I were far past brother-to-sister love. I sighed inwardly.

So much for seeing other people until we worked stuff out.

"-should go. Dinner's in a few anyways..." I heard Alex say.

"Huh?" I asked.

"I said I think I should go. Dinner's soon and Mom hates it when I miss dinner. Uhh..I guess it was...nice? Hanging out, I mean..." He looked at Derek and merely nodded his head. "See you tomorrow!" hHe called as he went out the door.

"Oh God..." I whispered quietly.

3…2…1…

"Wait...tomorrow? Mer, tomorrow's Saturday...why would he see you tomor - " he trailed off. "Oh. You have a real date." He got up and started down the stairs towards the door.

"Der! Wait Derek!" I ran down after him. "Derek I'm sorry. You said...so I just...and he-"

"You'll just have to cancel," he interrupted, pushing the door open and stepping out into the sunshine.

"Yeah. I'll just have to - wait what?" I asked, replaying his words in my mind. I stepped out the door after him.

"Cancel. You'll just have to cancel." He looked at me like it was the simplest thing in the world and began to walk around to the side of the house.

"Wait! Who the hell do you think you are?" I called, running after him. "Since when do you get to tell me who and when I associate with! You arrogant jackass!" he spun around.

Uh-oh. Oh God...I crossed the line with the jackass thing, I just know I did.

"I mean..." I started again.

He actually looked pissed. "Why should you get to tell me if I can go on a date or not?" I tried, quieter.

"Since. You're. Mine." He growled, and before I could even ponder what he was saying, I was against the wall.

His lips were against mine in a bruising way, much like my back was against the brick of the house. I felt the vibration of his moan in my mouth as I got caught up and ran my fingers through his hair, fisting it roughly. His mouth slipped down to my jaw line and from there, to my neck. I heard him growl from deep within his chest as he pressed hot, wet, open-mouthed kisses to my neck and throat. I whimpered quietly when he nipped me. He worked his way to my ear, where he sucked on my earlobe gently and whispered into my ear.

"Like I said. You'll. Just. Have. To. Cancel." he backed off a little then, and I found that I couldn't function. He was trying to hand me something. I realized a second later that it was my cell phone. I took it and stared from him to the phone, then back again.

"Well, how will he know the date's off if you don't call him?" he asked logically.

Good point.

As I scrolled through the 'a's' in my contacts, I felt myself hoisted up against Derek and I instinctively wrapped my legs around his waist as he pressed me back against the wall. I heard him groan quietly and I giggled. I finally found the number I was looking for and hit send.

D POV

Feeling Meredith's legs wrapped around me was like nothing I had ever dreamed of. The heels of her feet dug into my ass slightly and she had one arm draped around my neck. I heard the ring of the phone and set to work, sucking gently on her neck. Her eyes closed as her head fell back against the brick.

"Don't hurt yourself babe," I found myself mumbling quietly.

"Al-Alex." she started. "Listen, my brother came home." She stopped talking and I assumed I had found a particularly good spot on her neck.

Duly noted…

I backed off and she started again.

"He came home and said that we have plans all this weekend and that I can't do anything. I'm really sorry and I hope we can catch up some other time." At the last sentence I nipped at the sensitive spot on her neck, and she moaned as he talked. She quickly said her goodbye, and hung up, tossing the phone onto the grassy ground behind me.

"I hope he heard that last bit. Maybe he'd get a freaking clue." I grumbled.

"God you're horrible, Der," She giggled.

"Horrible? Horrible?" I feigned hurt. "I'll show you horrible," I growled playfully before I kissed her again, pulling on her lip and nipping it.

"Der, believe me. That's anything but-ahh. Anything but horrible." she finally finished. She then leaned back, looking into my eyes. "We're crossing the line here, Derek. Definitely crossing the line." she finished with a sigh.

I chewed on her ear gently as I mumbled, "This line. Maybe we should make it clearer. I could get you a marker...or sidewalk chalk or-" I didn't get to finish because of the playful hit Meredith swung at my chest. "Okay, okay," I said, laughing, "you're right, we're definitely crossing the line. But Mer?"

"Yeah?" she asked.

"You're forgetting; I live for danger." I smiled and gave her one last kiss before I set her down on the ground and followed her back into the house to wait for Mark.

A/N: Reviews are better than jealous Derek!