Disclaimer: I don't own anything of Teen Wolf.

Note: It has been a while since I have been in the Sterek fandom, wow almost two years. So why not grab the chance when the Sterek Secret Santa is being hosted. Let's see about having some fun. This is inspired by the Rocky Horror Show.

Recipient of this gift: paintedrecs

I hope you enjoy your secret Santa gift

Warnings: slash (obviously), AU warning, sex.

Title: Christmas surprise

Summary: Derek gets a surprise from an unexpected source and a very early Christmas present.

Derek was suspicious. Hell that may even be the wrong word. He was always suspicious. That was what being betrayed by your girlfriend who set his house on fire and killed off most of his family, being betrayed by his uncle who tried to kill him many times to try and become the alpha, having a beta who didn't trust him and then finding out that various members of his family had survived the fire, being used and almost being killed multiple times did to you. Perhaps the better word was that Derek was paranoid. Especially now that everything was finally going his way for once. The past winter had been fine, yes happier people would call it spectacular since everything was quite, his pack was doing well and Derek found a job he enjoyed but Derek would never admit to anyone that everything was well. There was always this little voice in the back of his mind that there was something worth worrying over and in this instance, surprise, surprise it came from within Derek's pack himself.

And it wasn't even anything in particular that his pack or Stiles did since it concerned him. No, it was more something that Derek's wolf was doing which was causing him some concern. Ever since Stiles Scott, Lydia and Jackson had set of for college and universities across the States, thus scattering Derek's pack to the four winds for most of the year, Derek had found himself oddly possessive of his pack members when they were in Beacon Hills. While that in itself was not surprising, considering he was an alpha and thus needed his pack to centre him, he found himself more possessive of Stiles. So when his pack members came home smelling of foreign people and places Derek always rubbed up against them in wolf form, that was okay, his betas understood and did the same thing so they could share scent and surround themselves in the scents of pack and home. They often formed a puppy pile on the first day everyone was back in town, Derek in wolf form, Jackson and Scott fully wolved out, the same with Erica and Boyd, and Lydia and Stiles in the middle of it. It helped Derek when his pack was complete. It had been better last year when Boyd and Erica were still in high school but now that everyone was attended college it was harder. But Derek coped because he knew that his pack was always together for Christmas, Easter and during the summer. His pack was alive even when they were not in the immediate area.

No the most concerning part was that Derek was starting to be particular possessive of Stiles, even more so then any of the others. When he had begun displaying the behaviour a year ago, Derek had dismissed it as a normal behaviour on his part, but now the second year he had begun to realize that he had started to think of Stiles as his mate. It had taken a while to realize that the scent that was so appealing to him and which always clung to Stiles, the scent of belonging and home, was the scent of his mate. And with Stiles being away at college and often dating and doing all sorts of things, Derek was fucked and sadly not literally.

So he was very surprised when he slammed his camero door closed and started up the steps to the renovated Hale house to find the door ajar. It wasn't that he was very fussy with his locks, all of his pack members had a key to his house and an open invitation for them to visit and crash whenever they wanted or needed to but this was different and Derek sniffed the air suspiciously. All his pack members should still be away at college since it was just the Monday after Thanksgiving weekend and while they had been down for that, they needed to finish up their semester. So why was the door ajar?

He started up the stairs to his house in a stalk. His eyes flashed red and he could hear the heartbeat in the house hammer away. It sounded familiar, very familiar. He frowned, why was Stiles here? He should be in New York at Columbia, being his smart, sexy, energetic self and making people fall in love with him. Derek closed his eyes, he had just not thought that. This was getting out of hand, he needed to sit down with his wolf and have a proper chat.

But right now that was who he needed to have a proper chat with. No that was Stiles because seriously why was he here in Beacon Hill when he should be on the other side of the country to finish his exams?

With a growl, Derek stepped into the living room, ready to give Stiles a piece of his mind. His words died in his mouth the moment he beheld Stiles. Normally, Stiles was delectable and lickable enough for Derek but right now….bloody hell, there was no other word for it, he looked gorgeous.

Stiles was dressed in a red corset, with jeans on and sneakers. The grin he wore was a flirtious one and not one that Derek had ever been on the receiving of end of unfortunately. He bit back a whistle and then cleared his throat as he said. "That is not what you normally wear when you go out in public is it? If so then university certainly changed you."

He grinned and his eyes flashed red. His wolf was very close to the surface and he had trouble controlling it.

Stiles smirked and it send Derek's heart racing before the younger man ran a hand down his chest and said. "Well they do always say that you need to experiment in college. Let's just say that I discovered some things about myself that I thought that you might appreciate…"

Derek swallowed and then growled. "And why would you think that I would enjoy this? I am quite that your experiment would not be so keen to know that you are continuing this experiment with another man, your alpha for that matter."

For the first time Derek noticed a hint of uncertainty cross the handsome face. His wolf whinnied in responds before Stiles said. "If you really didn't like the way I looked, which is amazing by the way then you would have tossed me out of here by now. I have known you for years now, Derek."

"Fine, I'll admit that you look good…"

"Amazing…."

"Fine amazing, now that still makes me wonder why you are here, dressed like that." Derek took a step forward. His hands were itching to stroke the material covering Stiles' chest and despite the fact that his wolf loathed that Stiles had been with someone else who had taught him these things instead of Derek, he was curious to see what Stiles had learned. It must take the other man nerve to stand there like that in front of Derek, not knowing how he was going to respond and looking like that.

"Like I said, college is good for experimenting and figuring out what it is that you want. It also teaches you to go after what you want and how to do it. So here I am, putting myself on the line and hoping to fly. Will you make me fly, Derek or fall?"

That was all the reason Derek needed and he stalked forward, eyes red as he said. "I am not going to make you fly, Stiles because that would mean I would let you get away. No, I intend to make you scream as I take you and make you mine."

His hands came to rest on jeans clad hips and he pulled Stiles forward, finally claiming his mate's lips in a kiss. His wolf went quiet inside him and relaxed, savouring the taste of his mate. Stiles kissed him back enthusiastically, wrapping an arm around Derek's waist. The kiss deepened and they stumbled as Derek tried to get the upper hand. Finally the need for breathe became too dire and they broke apart, panting.

Stiles grinned and said. "Finally…This was so worth it…."

He stroked the leathery texture of the red corset and Derek's eyes focussed on the movement. He was watching his prey and he would damn well eat it too. He stepped in and put his hands once more on Stiles' hips as he answered. "Oh, don't you worry about that. I will make it worth your while.

His mate's scent was pure arousal and Derek licked his lips. He knew his eyes were red but he couldn't help it. His wolf was very close to the surface and the close proximity of his mate was a balm to his nerves. For ones the wolf side of Derek and his human side were in complete agreement.

"Did you have anything else planned?" He growled, smirking at Stiles. The younger man met his smirk for smirk and said.

"Well I have several things planned but it kind of depends on you I suppose."

"I think that you may have to throw these plans out of the window since I am taking over…"

"Oh…." That was all that Stiles could get out before Derek stalked in, grabbed his mate around the waist and walked him back against the wall. Stiles' eyes were wide as Derek crowded him against the wall and kissed his way down his throat, keeping him in place with his own body.

He marked Stiles' throat and growled. "Mine…You are mine, Stiles. Is that understood?" He pulled back to see Stiles nod and then said, holding the younger man's eyes. "Tell me to stop now if you do not wish to be mine because once I mark you as my mate I am not letting you go, ever! And I do not intend to share." It went unspoken that Derek and his wolf both would never recover if his mate betrayed him.

Stiles held his eyes and then he said. "I understand!"

Derek was sure that Stiles did. The younger man had a way of knowing the important things and understanding them in a way a member of his pack would have. He buried his face in Stiles' throat, licking at the exposed flesh, nuzzling as he struggled for control.

Stiles' hands ran through his hair and down his neck, the touch calming him and arousing him. He shrugged against his mate and he lifted his head to claim his lover's lips. Stiles kissed him back and as Derek broke the kiss for some breath, panting through lengthening fangs, Stiles said. "Claim me, mark me, Derek. Make me yours!"

"Are you sure?" He had to know because there was no going back. Stiles bit his lip and nodded. Capturing another sweet kiss Derek smiled. His mate's brown eyes met his and Stiles gave another nod. It was all the encouragement Derek needed.

His clawed hands ran down Stiles' side to his jeans clad hips to travel down his thighs. He applied pressure to get Stiles to lift up his leg and wrap it around Derek's waist. He widened his stance to balance their weight against the wall as he took his mate's mouth in another kiss. His claws made it difficult to fumble with Stiles' belt but Derek could not control himself. He growled into the kiss and Stiles patted him, sliding down so he could do it himself.

"Calm down and undo your own jeans before you end up breaking my jeans. While ripping of my clothes is all kinds of awesome I am rather attached to the jeans. I am a poor student, I don't have the money to buy new clothes, especially if this becomes a regular thing and I may be forced to fly out…." Stiles finally stopped talking as Derek kissed him. He kicked his shoes off and undid his jeans, ripping off the fly in his haste before attacking Stiles' jeans with equal passion.

"I'll get you a new pair." He murmured in between kisses as he walked Stiles' backwards against the wall. His mate was prey and Derek had every intention of eating him, in one way or another. He smirked as he met the brown eyes of his mate and nuzzled at him as he said. "My wolf is in control and my patience is razor thin. If you do not want this quick and rough then I suggest you…."

Derek howled when Stiles stroked him through his underwear. Stiles smirked and said. "Quick and rough sounds pretty good to me right now. There is plenty of time for the slow and thorough time later." He stroked a hand down his corset and Derek's eyes following his fingers. When Stiles reached behind him to undo the corset he stopped his mate.

"Get rid of the rest of your clothing but keep that on." He nodded towards the corset as he made a move to kick his jeans off but Stiles said.

"If you keep your jeans on cause that will be hot to be fucked by you against the wall with your jeans on. It is a fantasy of mine." Derek's head snapped up but he inclined it. He would be able to give his mate that much at least, as well as equal pleasure.

Stiles kicked his jeans away and did the same with his boxers and Derek took the time to appreciate the view. Stiles was beautiful and he made a appreciate wolf whistle that had the younger man blushing and grinning. Derek frowned when Stiles tossed him a condom, he glanced down at it and then nodded. He began by tearing open the package and putting it on. His eyes flipped closed as he fought for control while slipping on the condom. When he was sure that he would manage he opened his eyes to find a vision that caused his control to slip entirely.

Stiles was preparing himself. His lover had put one leg up on the couch for better reach and….the sight send Derek almost spiralling out of control. He waited until Stiles was done before stalking forward, grabbing Stiles by the shoulder, spinning him around and lifted his legs up to encourage him to wrap them around his waist. He kissed Stiles, all tongue, teeth and growls but he didn't care. It felt so good.

He balanced tem against the wall and he softly asked. "Have you prepared yourself properly? I'll go slow, I promise, bear with me…."

Stiles nodded against his throat as Derek lifted him higher, angling them properly so his cock lined up with Stiles. He braced against the wall and buried his claws in it, not caring for it. He pushed in slowly, his breathing harsh against Stiles' throat as he licked at the exposed flesh. Stiles gasped as he pushed in and Derek paused. His beloved's eyes flew open and Stiles moaned. "Don't stop."

Stiles' hand dug into his shoulders and Derek lost control. With one last growl he pushed in, burying his claws in the wall behind him for extra leverage as his other hand tightened around Stiles' hip before they began moving in an age old rhythm.

All Derek registered was the heavy breathing, breathless moaning, words that lost their meaning and the feeling of being buried in his mate that was just so right. They were lost in each other and he came with a shout as Stiles climaxed, following his mate. He must have blackened out because he came around as Stiles petted him. His claws were buried in a shredded piece of the wall and he frowned at it, had he done that?

Stiles winced and said. "While I am all for after cuddling sex my leg is starting to cramp." Now that was not acceptable so Derek moved them towards the couch. His wolf was happily tuckered out and Derek wanted to take care of Stiles. Within moments he had them both on the couch, hands running to ease the cramping. He was getting sleepy and he nuzzled in Stiles' scent, the scent of his mate.

"So this is a thing now?"

He merely nodded and said, lightly licking the other man's skin. He nuzzled at the corset and said. "If it means that you wear more corsets then yes, this is a thing." He smirked up at his lover, happier then he could ever remember. Stiles rolled his eyes and said.

"Fine, I'll do that if you promise to love me for the rest of my life…" He grinned as he batted his eyelashes.

"You'll never get rid of me, you are mine." And as Stiles kissed him, Derek knew that Stiles' unexpected visit had been a very welcoming surprise indeed.

I hope you liked your gift. I had a lot of fun writing this in between my busy schedule.