A/N: Warning: herein lies lemon.

Misaki was turning down the covers of the bed when Hei walked in. Her bedroom was modern in style, all smooth, clean lines and efficient use of space, dressed up in cool blues, grays, and white, with a splash of cheery yellow here and there. The silver metal headboard of her bed formed a pattern of geometric squares, an industrial look that was softened by her gray-blue duvet. Deep blue curtains framed the window, hiding the blinds and the scarf hanging behind them. It was the perfect oasis from the stresses of her daily life.

The only light came from a small, swing-arm reading lamp screwed into the wall above the bedside table. It cast a warm, diffuse glow around the bed. Hei had seen the room in such an atmosphere many times before, but never with his mask on. Now, the space seemed strange, full of shadows - foreign somehow, as if it wasn't the same room at all. Maybe it wasn't.

Misaki, still occupied with the bedding, looked up at him sharply. "Wait there."

Hei halted obediently just inside the room, and watched with a nervous amusement as she smoothed out the folded duvet and plumped the white-cased pillows. She was stalling.

Then she walked around the bed and came face-to-face with him, arms folded, and he stopped being amused. Save for those top two buttons, she was still fully dressed. With her hair tied back and her warm brown eyes partially hidden behind her glasses, she was every inch Section Chief Kirihara. Hei's heart pounded in his chest. This was the woman who just hours ago had stared into the face of death at the hands of the Black Reaper without so much as a flinch. She wore that fierceness now, and it made his blood rush straight to his groin.

Misaki looked him up and down, as she had out in the main room, and walked a slow circle around him. He felt a slight tug on the chain linking the handcuffs together; she was checking to make sure he'd secured them properly. It made him nervous to have her behind him like that, though he didn't know why. She completed her circuit and stood in front of him once again. Her lips pressed into a thin line as she gazed into the eyes of his mask for a long moment, and he wondered if she was going to call for backup to arrest him after all.

But then she reached a hand up to his mask. He felt a slight, moving pressure on his right cheek, and realized that she must be tracing the path of the purple lightning bolt.

"BK-201," she murmured. "I have you, exactly where I want you…so what am I going to do with you?"

That was strange; usually when they were together, she did her best to pretend that he wasn't the Black Reaper. He felt the gentle touch of her fingers at the interface between skin and mask. Slowly, she ran her fingertip along that edge, barely brushing his skin, all the way down to the tip of his chin. Her expression looked fascinated, as if she'd never seen him so close before. His breath hitched; he ached for her to remove his mask so that he could take her lips in his own.

But she didn't. Misaki's fingertip continued on a path down his throat and over the collar of his skin-tight shirt. While she traced random patterns on his chest, she slid her other hand up behind his head. Weaving her fingers into his hair, she tugged sharply so that he tilted his head back and he felt her warm lips on his throat. She kissed him lightly, delicately; the touch of the tip of her tongue sent a shiver down his spine and he strained against the handcuffs that prevented him from holding her.

"None of that," Misaki warned in a low voice. Her grip on his hair tightened painfully. "It'll only go harder for you if you struggle."

He wished that she hadn't said that word. His arousal was already uncomfortably constrained within his shorts; it wasn't the struggling that was making it worse.

Misaki's hand was now making a circular motion just below the side of his ribcage, and Hei realized with a start that her movements weren't random at all. She was tracing, through the cloth of his shirt, the invisible outlines of his scars. She knew each one by touch alone.

She finished with the scar under his rib, and trailed her hand further down. His skin was hot and prickly beneath the stifling mask - when was she going to let him out of the cuffs?

Not any time soon, it quickly become apparent. Her hand skipped over his belt and went straight to the bulge in his pants. She squeezed and caressed him through the black fabric, alternating a soft, tender touch with an almost painful grasp. He groaned with each movement of her fingers, the sound muffled behind the mask.

"Do you want me to let you out?" she murmured into his neck, her breasts pressing against his chest. "I can…or I can keep you trapped, and torture you like this all night." She tightened her grip, and he gasped. "You're in my complete control."

Abruptly she let him go, releasing her hold on his hair as well, and turned her focus to his belt. Hei, his breathing getting heavier by the second, watched her remove the gloves that he had tucked there and drop them onto the floor, one at a time. Her face was just as flushed now as he was sure his own must be. She threaded her hands around his waist, between his back and his bound arms, and deftly undid the clasp that had given her so much trouble that first time she'd undressed him. The ends of the belt snaked through the belt loops as she pulled it forward. It dropped to the ground next to his gloves.

Misaki rested her hands on his hips, toying with the waistband of his pants. He loved the fearless way she touched him; he was dying for her to lift his shirt, to feel her warm hands on his bare skin.

A sudden frown creased her face. "I thought I told you to leave your all knives out there," she said.

All…she must mean the small dagger on his leg. He was still wearing it.

"I forg- " The slap took him by surprise; his mask shifted slightly where her fingers caught the edge of it, his jawline stinging from the blow.

"I didn't say you could speak!" Misaki snapped, shaking her hand a little.

Hei had never seen her so angry, on the verge of losing control like this. He was torn between the desire to take her hand in his and try to soothe away her pain, and the urge to seize her by the wrists and imprison her in his arms, where she couldn't hurt herself again. Either move would probably just anger her more; but it didn't matter, because he was in no position to do anything except stand there and let her have her way with him.

Misaki roughly unbuckled the strap holding the knife to his leg and threw it to the side. With just as little ceremony, she tugged his pants down over his hips and let them drop to the floor. Gripping the waistband of his undershorts, she pulled them down, freeing his erection at last.

Her eyes were fixed on his, as if daring him to make a move or object. She took him in her fist and began slowly pumping the length of him. Hei sucked in a sharp breath at her light touch. As good as it felt, though, it wasn't enough. He needed his hands in her hair, her legs wrapped around him. He needed those damned cuffs off.

Then she glanced down. Without letting up, she sank to her knees in front of him. She'd offered to do this for him once before, when she was on her period and too uncomfortable to have sex. He'd declined; he hated the idea of her doing something so intimate and pleasurable for him without getting anything in return.

"You don't have to -" he tried, and the smack that left his bare ass stinging had the full force of her arm behind it.

"That was your last warning," she said, her voice dangerously low. Then she wet her lips, and took his tip in her mouth.

Hei closed his eyes, struggling against the sensations that were flooding his body. Her mouth was gliding up and down him now, taking him deeper with each stroke, her tongue caressing the underside of his shaft. His hips rocked forward involuntarily; her nails dug into the back of his thigh in what he was sure was a warning not to move again.

Her speed picked up slightly; Hei risked a glance down and was shocked to see a look of pleasure on Misaki's face. It had never occurred to him that she might have been offering in the past because she wanted to do it, for herself. Seeing her so wholly consumed with the enjoyment of her task brought him quickly to the edge and he shuddered, trying desperately to restrain himself.

Misaki must have picked up on his desperation, because she pulled away abruptly, rocking back on her heels. Hei was a little relieved, despite his aching need.

"On the bed," she directed in a husky voice. She gripped his forearms to pull herself up, a little unsteadily, then gave him a small push towards the bed.

He made his awkward way over and sat. The cool sheets felt good on his still-stinging skin. Using his cuffed hands to steady himself, he positioned himself in the center of the mattress and waited, wondering what she had in mind.

Misaki couldn't see his eyes behind his mask, but she nevertheless held his gaze as she slowly unbuttoned her pants. She was torturing him on purpose, he was sure; she knew that he loved to undress her himself. He could imagine the feel of her smooth, firm skin beneath his hands as he watched her tug the garment down over her narrow hips. She stepped out of the pants, exposing long, gorgeous legs. How long had it been since his lips had last touched those legs, making their way up to her center, one delicious inch at a time? Two days, at least. Too long.

The tails of her blue shirt covered most of her panties, but as she walked towards the bed he caught the occasional flash of crimson and black lace. She must have bought something new. Hei took a deep breath, trying in vain to control his body's reactions to the prospect of seeing her in new lingerie.

Misaki climbed onto the bed and straddled him, holding onto his tensed biceps for balance. Her blouse was still buttoned save for the top two, hiding away her full breasts. Hei angled his head, hoping for a glimpse, but she grabbed his hair and jerked his gaze back up to her face.

"Eyes here," she ordered, and ground her hips forward, trapping his erection between her mound and his stomach. Hei's groan caught in his throat. Her glasses slipped down on her nose a little as she rolled her hips again and again. The contrast between the starched fabric of her shirt and the silky lingerie on his sensitized skin was exquisite.

Hei could see the strain on her face as she tried to ignore her own growing arousal. Finally she placed a splayed hand on his black-shirted chest and pushed. "Lie back," she said, panting a little.

He did as she told him to, his bound hands forming an uncomfortable knot beneath the small of his back. Above him, Misaki took one finger and pulled aside the lacy crotch of her panties, revealing her swollen and glistening labia. Hei could hardly breathe beneath the mask now. With her other hand, she guided his tip into the entrance of her slit. He felt her silky wet folds caressing him, and it was all he could do not to thrust up and into her. A slight smirk played across her lips, and he was sure that she could sense his impatience.

But he resisted. If this was what she needed, then he would let her take it.

Misaki teased him for another long minute, shuddering a little every time her movements brought him brushing across her clit. A few strands of her hair had come loose and were sticking to her sweat-dampened forehead. Hei could feel his resistance crumbling around him, and held on with every ounce of control that he had. Finally, with a low moan, she pushed down; the feel of her hot, tight sheath encasing him drove the breath from his lungs.

Hei couldn't take his eyes away from her face now. She leaned slightly forward over him, bracing herself on his shoulders. Her glasses slid a little further down her nose, giving her face a sharper, more angular look than he was used to seeing when they made love. Her eyes were closed, her lips parted; if his hands hadn't been restrained, he wasn't sure he'd be able to stop himself from throwing her down beneath him and pounding into her until she came, shouting his name. Each rocking movement of her hips brought him closer and closer to the edge, each squeeze of her internal muscles threatening to send him over. He'd never been so frustrated in his life as he was now, at his simple inability to touch her.

She twisted her pelvis in a motion that she knew drove him mad, and the tiny gasp of pleasure that escaped her throat was suddenly too much. His hips twitched involuntarily and he came inside of her with a guttural moan. Misaki's breath caught in surprise; she pumped up and down once, twice; then she leaned her forearms against his heaving chest and opened her eyes.

"Fuck," she breathed, looking completely exhausted and not at all satisfied. Her hair fell across his face, but he couldn't feel it through his mask. She raised herself up a little, releasing him and tugging her panties back into place. Her inner thighs were wet and gleaming.

Misaki stared at him pensively for a moment as she brushed the hair out of her flushed face, then averted her eyes and said softly, "I'll go get the key." She rolled stiffly off the bed and padded out of the room. Hei watched her go, noting the way she pulled her shirt down to make sure that it covered her beautiful, tight ass.

He lay back, staring at the ceiling as he tried to catch his breath. She hadn't come; and even though he had, it somehow felt..off. Wrong. As if she'd taken his release from him by force, rather than him giving it to her. He'd had his physical relief, but emotionally he felt more bereft and alone than he had waiting outside her building, wondering if she still cared anything for him. If she'd stayed, he could have finished her; he didn't need his hands for that. But somehow he didn't think that it would have been very satisfying for either of them.

His hands were starting to go numb beneath the weight of his body. She hadn't needed to restrain him - he was already hers.

Why had she? He always let her take the lead in the bedroom - she liked being in charge, and he was used to taking orders. It was easier that way; he didn't have to worry about hurting her or frightening her by accident. It wasn't usually a problem - they both preferred tender, mutually-pleasing lovemaking. But tonight, she'd clearly wanted something different, and he didn't know what it was.

Except…she'd called him BK-201. She hadn't called him that since before she'd found out who he really was. She'd wanted the Black Reaper here tonight, not Hei. He remembered the exhilaration of their earlier standoff, the deadly determination in her eyes as she faced him down and he waited for her to shoot him, and his pulse immediately quickened again.

Hei was BK-201; it was easy to forget, when he was with her. He never should have let her put those cuffs on him.

But she hadn't, had she. He'd done it to himself. That had been his mistake. And hers.