Disclaimer: I don't own anything.

Warning: Yaoi. Lemon. SteinxSpirit. Don't like, don't read. I'm going to warn you now that I'm going to try to keep these two in character, so if you don't like the implications of that, I suggest you stop now.

A/N: Okay, so this is my first Stein/Spirit fic. So, sorry if it's crap. Um, I think it's going to be a oneshot, I don't know. I'm working on some other things right now, but I think once I'm done being horrendously busy I might write a more proper Stein/Spirit fic. Okay, anyway, on to the story.

Stein sat in front of his computer typing away and giggling manically as he felt the madness consuming him. He tried to fight it at first, tried to stay focused, but letting go and letting the insanity consume him just felt right. It was something he had known about himself for years. He was not so foolish as to believe that wanting to dissect everything he looked at, experiment on it, harm it, and put it back together was normal. He had known there was a darkness about him since he was a teenager, and he had learned to control it for the most part. Having Marie sleeping soundly, so very vulnerably within the comforts of his own home was beginning to test that control, however, and that coupled with Asura's maddening aura… it was becoming impossible.

He stared at the screen before him still laughing hysterically at his own thoughts. It would be perfect. He just had to wait until she fell asleep, or he could drug her tea or something stupid woman seemed to have a fetish for tea. And she probably wouldn't even notice, if he just played along with her for a little while, told her how much she meant to him or some meaningless heap of crap like that. She'd fall for it. No matter how much she tried to hide it, Stein could tell the blonde still loved him, for what reason he couldn't even begin to fathom, but it worked for him. If she was distracted enough by the prospect of love and marriage and early retirement, she probably wouldn't even suspect anything. And then he could open her up and poke around. She was such a strange specimen, it was sure to be interesting. He hadn't really realized how loud his laughter had become until he felt a hand on his shoulder. He had been at least loud enough to drown out the sound of this person's entrance.

"Stein-san, are you okay?"

Stein calmed his laughter managing to restrain himself to small giggles and chuckles rather than the booming laughter that had been erupting from him moments before.

"Fine… Marie-chan." He drawled her name out slowly… in an alluring tone he hadn't even been aware he was capable of. He continued to giggle slightly trying to calm himself down. Marie blushed and fidgeted slightly; Stein took note of the faint blush on her face and smirked to himself. It really was too easy.

"Um, well, I'm going to go see Azusa. Oh, and, um, Spirit-san is here to see you." Stein nodded and furrowed his brow. Spirit was not who he wanted to see right now. What he really wanted to see were Marie's insides sliding through his fingers soaked in blood and… he started laughing again, Marie turned giving him a concerned look.

"Go ahead and said Spirit in." he said, his laughing calming once again as he caught himself. Marie nodded and hurried out to the living room, where Stein assumed Spirit had been waiting. The door closed in indication that Marie had left, and Stein relaxed. At least her departure would give him time to drug her tea.

Spirit walked into the dark room with his shoulders drooping and his feet shuffling slowly. He looked as though Maka had just given him a good scolding, which she most likely had.

"Hey Stein?"

"Yes senpai?" Stein didn't bother trying to hide the venom in his voice.

"Have you been feeling alright? You've been acting a bit strange." Spirit asked slowly.

Stein simply glared in response.

"Maka-chan's been yelling at me to come make sure you're alright, she's really worried." Spirit admitted blushing and looking slightly worried. Stein could tell the redhead was replaying his tongue thrashing in his head. Spirit even flinched a few times, Stein just sat watching him, looking bored.

"I'm fine." Stein replied in a distant voice as he was suddenly overcome by the imagery of his past experiments, how wonderfully intricate Spirit's innards were… He was not opposed to digging around inside the man once again, and it'd make for such wonderful practice for when Marie came home… but suddenly Marie's insides seemed so much less… attractive. He wanted Spirit. He smirked sadistically, a look Spirit had come to know quite well.

"You know, I think that's enough. I'll just be going now…" he started to back up slowly towards the door, but found he couldn't move. He looked down at his feet to find small blue glowing stitches sewing him to the floor, not allowing him to move.

"Why don't you stay awhile?" Stein's smirk grew into a crazed smile as he stood and stalked over to the redhead, his coat flowing menacingly behind him.

"Stein, I really think I should go, I just came by to make sure you're doing alright…" Spirit tried to think of a way out of the situation, but he knew Stein well enough to realize that it was futile. Stein wanted something, and chances were no matter what he said he was going to end up cut open and rummaged through.

Stein chuckled, a deep throaty sort of sound. "Don't worry. It'll only hurt for moment!" Stein all but laughed, his voice maniacal. Without further warning Stein stepped forward and cut a gash into Spirit's stomach with a medical tool, Spirit assumed was a scalpel, though he had no idea where the instrument had come from.

His thoughts left him as he felt the pain of the wound in his abdomen finally set in. He gritted his teeth and clenched his fists to keep from screaming out in pain. Stein had never been insane enough to do this to him while he was actually awake. It hurt like hell, and he couldn't help but double over in pain.

"I'll be with you in just a moment." Stein chuckled to himself, as he pushed an operating table behind Spirit, releasing the soulthread stitches, and pushing his patient backwards so that he landed on said table. The soulthread stitches went to work once again, stitching Spirit to the table as he giggled excitedly. "It's been such a very long time since I've been inside you… I wonder if anything has changed Spirit-kun!" Spirit tensed at the implication. He had known that Stein had done…things. But never allowed his mind to ponder over what exactly had happened when he woke in the morning feeling sore and strangely sated. He cringed realizing his fears had been well placed.

Stein none too gently inserted a finger into the gash painting Spirit's abdomen and alluring shade of red. He heard himself giggle distantly as he fished around, feeling something particularly interesting, Stein pushed further inside of Spirit, gripping whatever organ he had found and fishing it out. Spirit's screams of agony only egged him on.

"Look what I found Spirit-kun! How long do you think you'd live without this?" Stein began tugging at what Spirit assumed were his intestines. They were long and slimy… slick with blood. Spirit felt himself getting sick. "Now, now, don't you pass out on me senpai." Stein laughed. "Okay, okay, we'll save the removal for later, let's find something we can cut into!" He let out another shriek of laughter, shoving the intestines haphazardly back in where they had come from, and stitched the wound closed with his soulthread stitches. Spirit had no time to be relieved. As soon as the first wound was closed another was opened, this time in his chest. He dug around in the redhead's chest giggling and playing around like a kid in a candy store. He toyed with everything he could get his hands on, switching things around until all of Spirits organs were on the wrong side of his body.

Spirit was sure that Stein had been talking and laughing, making morbid puns while he giggled, but he was just barely conscious, and couldn't actually process what was being said or done. He wasn't even sure if he was screaming anymore. His throat hurt, it was raw, and while he knew he wanted to be screaming, or pleading for it to end, he couldn't hear himself anymore. He wasn't really there. He was only conscious enough to feel a slight pressure in his chest, but it didn't really hurt. He looked around the room idly, everything was slightly fuzzy, and he was sure he was going to pass out soon. Probably from blood loss if not from the pain he could no longer feel. He felt himself slipping away, and suddenly there was a new sensation.

The pressure in his chest was gone, but he wasn't exactly sure that was a good thing. And then he felt, more than saw Stein leaning over him. It took a moment for his vision to focus well enough to see the man hovering over him, his glasses catching the light in just the right way to give him a crazed look. The smile on his lips didn't help any either.

"I'm going to take you now Spirit-kun. And you will be awake, you will feel it. And by the end of it you'll be begging me not to stop." Stein chuckled as Spirit came out of his haze. He was vaguely aware of Stein sliding his pants off, and he certainly hadn't noticed Stein removing his own clothes. And where had his shirt gone? Did Stein take it off while he was 'operating'? Or had he done it just recently and he hadn't noticed? Spirit decided he didn't care. In the end it made no difference. Stein was going to do whatever it was he wanted to do to him, and there was nothing he could do to stop it. Even if it hadn't been for the soulthread stitches holding him down, he doubted he'd be strong enough to move at this point, let alone fight back. He let his body slump down on the table, and prepared himself for whatever was going to come next.

Stein leaned back over the helpless body before him. "You were mine Spirit-kun. You should have never left me…" There was a faint disappointment in the crazed man's voice. "And for some stupid bitch… I'd never do that to you. Leave you like that, and she took away your daughter too." Stein smiled then. "You should have stayed with me. You belong to me. You always have. No matter how many new meisters you get… I'll always be your true owner." Spirit cringed at the words. "Not even Shinagami-sama can take you away from me." Stein chuckled slightly at that thought. Here he was hovering over the infamous Death Scythe. One of only eight in the world, and the only one Shinagami-sama deemed truly worthy to hold the title, and he was about to claim him for himself yet again.

Spirit looked away, not wanting to consider what he had heard, he didn't want to think about it. He just wanted this to be over. He felt Stein run a hand slowly down his chest, caressing the the sore skin where his wounds still bled weakly. He didn't need to look to know what was happening. Stein had coated his hand thoroughly in Spirit's blood, and placed a finger at the Death Scythe's entrance, his chuckling had stopped, and there was a seriousness about him that was almost more frightening than the maniacal laughter. Spirit closed his eyes as he felt the finger slip inside of him. There was a strange pressure, but it didn't hurt, in fact it almost felt good. Almost. He took a shuddering breath and braced himself. The finger moved in and out, slowly, teasingly, and Spirit fought to ignore the feeling it aroused in him.

He suddenly became aware of the hot breath on his neck, the light nibbles there. He was enjoying this, though he hated to admit it, even to himself. Stein was precise. Every movement made him shudder in pleasure. The doctor knew exactly how to touch him, and he couldn't control his body's reaction. A second finger slid into him, and he bit his lip to hold back a moan. He would not let Stein now how much he enjoyed this. He wouldn't give the man the satisfaction. And then he felt the intruding fingers hit something inside him that made him gasp, and his body arched up, wantonly. He desperately tried to swallow the moan that fell from his lips, but it was too late. Stein had won this.

With a grin, Stein lifted Spirit's leg, and propped it up on his shoulder, positioning himself at the redhead's entrance, his hand still slick with blood, he covered himself it, making sure he was slick enough to slide inside the body before him. Stein got a sick sort of pleasure out of seeing himself covered in his victim's blood like this, and he felt himself giggle without really realizing he was doing it. Spirit shifted slightly under him, bringing the doctor back from his thoughts. He grinned, and slid himself inside the man beneath him, slowly enjoying every shudder that ran through Spirit's body as he did so. Before he was fully seated he felt Spirit rocking back against him, silently begging for more. Stein was not so quick to comply. He pulled back out at an achingly slow pace, only to push back in, just as leisurely. Spirit let out a small whimper at the pace, and tried to shift his body to get more leverage. If Stein wasn't going to move, then he was going to do it for him, but his efforts were to no avail. He didn't have the strength left in him to move enough, to change the pace to something a little less torturous.

Stein grinned at the effort, leaning and whispering softly in the man's ear, "If there is something you want, just ask for it…" The sound of the doctor's voice alone was enough to make him shudder.

"H-harder…" he whispered noncommittally, it sounded ridiculous, begging when Stein was all but raping him. He knew that it wasn't really rape at this point, he was asking for it, begging, and he hated himself for it.

"Hm. I don't think I heard you." Stein responded casually, keeping his slow pace.

Spirit broke then. He couldn't take it anymore. "Harder!" He yelled, there was a mix of anger and need in his voice, and Stein seemed to enjoy it immensely, which wasn't really the effect Spirit had been trying for, but when he felt Stein slam into him with a force great enough to make the table's metal structure moan in protest, all other thoughts were lost to him. He moaned loudly, and gripped the table beneath him. Stein grinned shifting slightly before thrusting forward once again, this time with aimed precision, purposely hitting the bundle of nerves inside him. Spirit gasped, and arched his back again, lost in sensation.

The movements became faster and more precise with every thrust, and it soon became clear that Stein too, was losing himself to the feeling of being surrounded so perfectly by his partner. The doctor was panting heavily, and holding Spirit close to him, in an unexpectedly needy embrace. His movements were becoming jerky, a sign that Stein wasn't going to be able to hold out much longer, and a hand reached between them, pumping Spirit's member at an unforgiving pace. Spirit had to fight to keep himself under control, as even the slightest movement brought him closer to his climax. One particularly violent thrust was all he needed, he came calling Stein's name, and muttering incoherently. His whole body convulsed, and the Stein lost his own inner battle as he felt the muscles tighten around him. He came with a strained groan, continuing to rock slowly for a moment as his climax ended.

With an exhausted sigh, Stein pulled out, smiling at his handiwork. Spirit had passed out completely, and while the helpless body before him was endlessly tempting, he was too tired for such things. With a groan he dressed himself, and Spirit, and took the buki home before Marie got back and questioned him about the naked bleeding man in his room.

The next day Spirit woke with the familiar feeling of being sore, used, and strangely contented. He sighed, remembering the events of the previous day. He slid out of bed, carefully, every muscle seemed to hurt, and entered his bathroom. Dreading what he would see, he flipped on the light and worked up the courage to look at his bare chest in the mirror. There were two large gashes across his abdomen that had been artfully stitched closed, but that wasn't what surprised him. On the right side of his chest, where he felt his heart had been moved to, the word 'mine' had been carved into him, and stitched closed in a way only Stein would have been able to do. He smiled at the discovery without really even realizing it.

A/N: Phew. End. Warped I know, but somebody had to do it. Thanks for reading!