A/N: Welcome to my big Railgun project!

Thank you to Cun for beta and for continuously supporting this story!

All reviews will be very gratefully received.

WARNING: Fanfic rated M: Please look at the rating. Then look at the genres. Now add Tragedy, Smut and Angst to the unfortunate mix. Are you sure you want to continue?

Fall into the Depths

CHAPTER 1:

"Hey, Kuroko…" She spoke out in a tentative voice. "If I was to cause a great calamity in this city, what would you do?"

Her junior looked at her curiously, and tilted her head for a moment as if to consider the possible reasons behind such a strange and abrupt question. A fine auburn eyebrow lifted and she threw a suspicious glance.

"Is this about taking juice from that vending machine?"

A bright blue spark crackled in annoyance.

"That stupid vending machine stole a 10,000 yen bill from me during my first year so it's fine!" The retort was sharp and fierce.

She let out a sigh, and calmed herself down before speaking again.

"No, what I mean is… something… something more… fundamental to Academy City than that."

Seconds ticked by as she waited for the inevitable response with bated breath. She watched her junior's expression flicker between confusion and worry before transforming into that familiar trademark determination of a Judgement officer.

"Onee-sama, I do not know why you ask me this question, but if that 'something' you speak of would disrupt the order of this city…" She placed a hand firmly over her heart as if to emphasise her point. "Even if you were my opponent, what I would do, would not change."

With her back towards Kuroko and her face turned away, Mikoto smiled in relief.

XXXXXXX

"Stop right there!"

Kuroko frowned as the fleeing figure disregarded her order and jumped over the railings. There was a loud explosion from the lower level, which rocked the entire building and brought up debris and dust. She looked over the barrier, her eyes squinted against the rising black smog to anticipate the hoodlum's next moves. A burst of light suddenly exploded from her right, and sent the teleporter reeling away. Her vision filled with white and she was swept by a wave of dizziness. She clutched her head.

'There was another one?!'

As she blinked frantically against the blindness, she sensed movement rushing towards her. Drawing on her past experiences, Kuroko took a deep breath and readied herself. It was all about patience and timing. Take the opponent by surprise. At the precise moment, she struck out efficiently with a low roundhouse kick. She smirked when she felt the heavy impact against her foot and heard a cry of pain. The whiteness was already starting to fade out from the edges of her vision much to her relief. She stepped up close to where she could vaguely see an outline of someone lying prone on the ground.

"Stop resisting and hand yourself over! This is Judge- ghh!"

Something sharp sliced the edge of her shoulder, and Kuroko staggered back with gritted teeth. Forcing herself to ignore the pain, she focused her clearing eyes upon her assailant who had gotten up and was running away. A quick calculation and she was suddenly in front of him, holding a foot out to trip him over. As he fell forward, Kuroko slammed a knee against his stomach. She felt something give inside the man as she struck down on his back with two clasped hands.

With a loud grunt, her opponent smashed to the ground, immediately falling unconscious.

Two quick swipes of her hands against the belts on her thighs, and the metal spikes hammered down along the edges of the troublemaker's clothes. Kuroko smirked. Even if he awoke, he wouldn't be going anywhere.

"Now, where did the other one get to?"

Right on cue, the radio earpiece around her head buzzed.

"Shirai-san, the target is heading towards the back exit on the ground floor."

"Right, pursuing him now."

Kuroko ran towards the railing, and sent herself hurtling over the edge with a flying somersault. She disappeared mid-air and reappeared at the far end of the corridor. She proceeded to run without pause.

"Keep going and then turn right at the first junction."

"Roger that."

Her injured shoulder ached and she could feel warm blood beginning to seep through her clothes. She shook her head. She had to keep her mind clear for the final leg of this chase. She teleported a few more times, quickly catching up to her target with every jump. Spotting him at the end of the corridor, Kuroko clenched her jaws in concentration for the next teleport. This was it; she had to capture this dangerous esper in one move.

She appeared behind him in a flash, and sent a fierce downward kick to the back of his skull. With a loud yelp, his face crashed onto the ground as the pig-tailed girl reappeared just a few paces away.

"Argh, you bitch!"

Kuroko's eyes widened as the hoodlum twisted his neck to face her, his expression dark and angry. Before she could move, the ground below them flared red and suddenly exploded outwards, sending the teleporter smashing into the far wall. She slid down and landed on the ground with a grunt, scattered bright stars erupting in her vision. She felt disoriented, but knew she was in a bad situation now; she had failed to knock him out in one shot. Kuroko forced her tired eyes to open as she squinted through the heavy dust, trying to see where he was.

"Shirai-san! Get out of there now! The entire roof is going to collapse!"

The voice from the earpiece was frantic. In alarm, Kuroko looked up, and her heart dropped to her stomach. A huge concrete slab had broken off from above, and was speeding down straight towards her. Gritting her teeth, she managed to teleport herself away just in time, although the distance was sadly lacking. The impact of the large object sent debris flying everywhere, beating down on her skin painfully. The whole building rumbled. The walls and the ceiling started to crack and crumble around her, breaking into tiny pieces. Kuroko leapt into action. She teleported continuously, pushing herself despite her exhaustion to concentrate on avoiding the falling pieces of detritus. Her top priority was now to reach safety.

The fresh outside air hit her as she made the final leap to the ground. She landed on her feet with a skid, breathing hard. She twisted her neck to observe the fate of the structure she had just vacated. It shuddered and then caved down completely, the two-storey building now nothing more than piles of rubble.

"Shirai-san! Are you alright?!"

"I'm fine," Kuroko replied as she dusted herself off. "Just a few scratches, but nothing that can't be fixed with a little rest."

"Oh good," her colleague at the other end breathed out a huge sigh of relief. "Did the entire building really collapse?"

"It sure did. Could you please tell Anti-Skill to check the site immediately? I'm not sure the espers in there survived, but if they did, they need to be treated and kept for questioning."

"Understood. Phew… that was a close one. Great work as usual, Shirai-san."

"It could have gone better, but I suppose we can't always have things our way," Kuroko sighed. She held back a wince as she tried to ease her injured shoulder. She adjusted the earpiece with a small smile.

"Thank you for watching my back… Konori-senpai."

XXXXXXX

"You should just go home and rest. It's getting late, Shirai-san."

"I already had my rest when they patched me up earlier, Konori-senpai." Kuroko did not turn around from the computer screen. "I want to make sure everything is in order before I go home."

Mii sighed at her junior's stubbornness, swirling a cup of coffee in one hand. She sat by the small table in their Judgement office and looked at the teleporter with concern.

"You need to know when to take a break, Shirai-san."

Kuroko did not reply. Her eyes continued to scan the list of names on the Data Bank without pause. A small frown marred her forehead as her fingers ran along the keyboard and clicked the mouse to find another entry.

"I mean it, Shirai," Mii said after a long silence. Her tone grew crisp, trying to capture the teleporter's attention. "You've been pushing yourself too hard lately. When I offered you the position as the next Chief of this Branch, it didn't mean you have to lock yourself in here every day!"

Kuroko hit the return key with more force than necessary. "I'm fine, Konori-senpai. I appreciate your concern but there is a lot of work to do. This case isn't going to solve by itself, and until the new recruits come in, there's just the two of us. We have to pull our weight!"

Mii's expression turned apologetic. She put down her mug gently on the table, and leaned back against the chair with another sigh. "I'm sorry I haven't been able to do much work recently. Final year of high school is turning out to be really hectic after all. We're already facing big exams soon."

Kuroko turned her head slightly and gave Mii a small smile. "It's perfectly fine, Konori-senpai. You decided to leave the Chief position so you could focus on your studies for university, right? Don't worry about the Judgement work and leave it to me."

"But–"

Kuroko shook her head, and let her smile grow bigger. "Leave it to the Chief now, Senpai."

Mii smiled back half-heartedly, although she still looked uncertain. She eyed the bandages wrapped around Kuroko's left shoulder and felt a twinge of regret in her heart. She still didn't know if she had made the right decision three months ago, when she offered Kuroko the position as Chief of 177th Branch of Judgement. A part of it had been a selfish choice, although she had no doubts that Kuroko would do an excellent job. No, she was more worried that Kuroko would burn herself out. Especially after all that had happened…

"Konori-senpai, did Anti-Skill state when I could visit the esper for questioning?"

Mii snapped out of her thoughts at the sudden question. "Ah… the light esper… His name is Minami Mitsuo, yes? He was unconscious when they found him in the rubble, so they took him to the hospital for treatment of course. They didn't specify, but I imagine you could speak with him very soon. Most likely tomorrow, since it really didn't seem like anything major. I think he was just knocked out by your attacks, and then got hit by some of the falling debris."

Kuroko nodded in agreement. "I left him on the second floor before the building collapsed." She paused to think for a moment and then typed something else into the computer. "I wonder what happened to the other esper though. It's bad news if he really escaped."

"He is a Level 4, right?"

"Minami Takeshi, Level 4 "Touch Detonator". He can explode anything he touches, which can get pretty dangerous," Kuroko grimaced. "Although he can generate a huge amount of force, his biggest weakness is that he's not completely immune to his own power."

Mii took a long sip from her mug. The quiet ticking of the wall clock could be heard in the silence before she spoke up again.

"Is there a possibility he may have died from the reckless attack he pulled?"

"It is possible," Kuroko said slowly, "but if he did die on site, I think Anti-Skill would have found his body when they searched through the rubble." Her eyebrows furrowed together. "It's actually quite troubling to think he made a suicidal move like that. He may not be very mentally stable. Perhaps he was growing desperate." Her eyes glanced at the file on her computer screen. "There isn't much information on him in the Data Bank, but it's obvious he is the older brother of Minami Mitsuo."

Kuroko exited the file with a click of the mouse. "If he is still at large, he may try to break his brother out from custody."

"Or even worse, cause another stir-up," Mii quipped, following her trail of thought.

The teleporter nodded. "The recent series of cases have been troubling me a lot to be honest. I know they are all linked somehow, but I just can't figure it out! Something about this also feels so familiar, but I don't know…"

Mii glanced at her junior as Kuroko slumped. Her eyes softened behind her glasses.

"I'm sure it'll come to you soon, Shirai-san. You have a real talent for detective work."

Kuroko spun around on her chair and faced Mii with a doubtful look. "I sure hope so, Senpai."

"The building that got attacked this time, what kind of facility was it?"

"It was a new power development facility that was going to be opened in about a couple of week's time."

"Just like last time, huh?"

Kuroko nodded. Mii noted how tired she looked; there were slight bags under her eyes, and her skin was quite pale. Her heart squirmed with guilt, and she found herself wondering yet again if she had made the right decision to pass on the Chief position. It was a great responsibility, Mii knew from first-hand experience. Kuroko took her Judgement work seriously. On top of that, she had gone through so much during the past year or so, Mii wondered if she was simply occupying herself with self-inflicted work as a distraction. The heart could take a long time to heal.

"This is the third attack on a power development facility this month, not to mention the other stray attacks on research centres. There may be more we aren't aware of too." Kuroko paused and continued hesitantly. "There is another thing that bothers me as well…"

Mii tilted her head in curiosity. "What is it?"

"In all three attacks so far, the offenders somehow got past high level security systems without a hitch. We only received the calls much later when people reported them. Some were outsider calls, while others were inside requests for help."

Mii leaned against the table, and stared outside the window. Some birds passed by the clear April blue sky, but she did not see them.

"Maybe there is a skilled hacker within the terrorist organisation behind this."

"Maybe…"

Kuroko abruptly stood up and walked towards the row of shelves that kept old records of past cases. Mii twisted her neck to observe her junior questioningly.

"Shirai-san?"

"I just want to check something, Konori-senpai." Kuroko took out a large folder, and leaned it against a cabinet before opening it. The book was a thick volume, labelled with the dates of most recent cases. She flicked the pages, and her eyes scanned over them carefully.

"Maybe there is something that could help us in here-"

A small piece of paper fell out of the folder. Frowning, Kuroko bent down to pick it up, turning it over to the front.

"What is this-?"

Her eyes widened.

Mii blinked. "Shirai-san?"

Kuroko didn't move. She stood gaping at something in her hand, and Mii noticed her shoulders quaking. Suddenly feeling concerned by her junior's strange behaviour, Mii stood up and approached her.

"Shirai-san?" she called her name quietly.

Standing behind Kuroko, she looked over her shoulder to see what she was staring at. She froze at the sight of an old photo in Kuroko's grasp. It was of four young girls smiling happily, enjoying each other's company. Laughter was in their eyes, their youthful expressions bright and cheerful. Amongst them was Kuroko, eagerly leaning towards someone she had once loved and truly cared about.

Mii's eyes softened. She laid a gentle hand on Kuroko's shaking shoulder and held still for a long moment. The photograph was on the verge of becoming crumpled by Kuroko's clutching fingers. Neither of them moved until Kuroko's quivering subsided. With a deep breath, the teleporter turned to face Mii with a hardened gaze.

"I'm sorry, Konori-senpai. This just took me by surprise."

Kuroko quickly stuffed the photo in her skirt pocket before Mii could say anything. The teleporter was suddenly all business again, shuffling through the pages in the folder. But Mii didn't miss how her fingers still trembled, and how red her eyes had become. With an aching heart, she realised her suspicions had been correct – Kuroko was still suffering, even after all this time.

'I must be a terrible Senpai.'

"Shirai-san, I think you should go home and rest."

Kuroko shook her head fiercely, her pigtails swaying from side to side. Her determined eyes remained glued on the pages filled with writing.

"But there is still so much to do. I want to go through some of these old cases for possible clues. And then I need to finish the report-"

"I'll do it," Mii said firmly.

"But-"

"I know you're the Chief now, but let your subordinates take care of things sometimes, ok?"

Kuroko turned around to argue, but faltered when she caught Mii's expression. Her Senpai was worried about her, and she realised her stubbornness was only making this harder for both of them.

"Konori-senpai…"

"Leave it to me, Shirai-san. Go home and rest."

Kuroko could only nod. She placed the folder back on its shelf and returned to the desk to grab her belongings. With a quiet word of parting, she left, feeling Mii's eyes on her back as she closed the office door behind her.

Now alone, Mii let out a loud sigh. It sounded hollow in the empty room. She stared at the far wall for a long while then moved to the computer, bringing up the report on the screen.

'Why did things turn out this way, Shirai-san?'

She could find no answer to her own question.

XXXXXXX

"I'm home," Kuroko called out as she entered her dorm room. Nobody answered, but she hardly recognised this fact.

Not bothering to turn on the lights, she kicked off her shoes and fell onto her bed. She buried her face on a pillow. She breathed in the floral scent of detergent, and listened to the silence around her mindlessly. Her bandaged shoulder ached and throbbed. It wasn't a big wound, but it still hurt where the thrown knife had grazed it. She also hadn't realised how exhausted she was until she reached home.

'Maybe Senpai is right…'

Kuroko turned her neck to face the other side of the room. She eyed the clock ticking away quietly, and then decided on a whim to skip dinner tonight. She wasn't hungry anyway.

Her gaze wandered to the empty bed, untouched by anyone for more than a year. One year and seven months now, she reminded herself. The neatly folded blankets were dusty, but Kuroko hadn't wanted to take them out. A large brown bear with a black eye patch sat propped against the headboard, also suffering the same neglected fate. She stared into its beady eyes as her hands curled into fists under her pillow.

"We're the same, huh?" Kuroko whispered to the stuffed toy. It offered her no reply.

She slipped a hand into her skirt pocket and dragged out the old photo she had accidentally found earlier. Kuroko smoothed out the crumples on the edges, and looked sadly at the bright faces of the four young girls beaming back at her. Her past self appeared almost surreal to her on the photo, so carefree and unknowing of what would happen.

'If only I had known back then…'

But what would she have changed? What could she have changed? The red strings of fate that had tied them together hadn't been strong enough after all.

Her eyes prickled. She quickly buried her face into her pillow once more. The photo fell from her hand, dropping down to the floor, but she made no move to retrieve it. She didn't want to look or think anymore. One year and seven months. Even after all this time, her confused feelings still hurt.

'I should get some rest. I have a lot to do tomorrow with the investigations…'

Kuroko lay on her bed for a long time, staring up at the ceiling. Sleep wasn't easy to come these days. As usual, her mind twisted and churned, and offered her no peace. She hated that she was like this, but she had no choice. With a sigh, Kuroko sat up and reached for a small bottle on the bedside table. She shook its contents out onto an open palm, glaring down at the white tablets before swallowing them whole. They tasted bitter on her tongue, even when she washed them down with water.

Closing her eyes, Kuroko lay back down on the bed. She could already feel the effects of the sleeping medication doing their work. A thick fog welled in her brain, sending her consciousness diving into uneasy dreams. As her sight completely faded, a single question floated in her swirling mind, desperately demanding answers.

'Onee-sama… where are you now?'

XXXXXXX

Minami Takeshi bit back a scream as terror threatened to swallow him whole. His bloodied features trembled in pain while anger and fright drove his heart into a frenzy. He could feel himself shake, and he clenched his jaws to glare up at the shadow leering over him. He couldn't afford to break down here, not after everything he'd already been through. Not because of a single girl.

A sudden brutal kick slammed into his chest, driving all air out of his lungs and sending his thoughts spinning. Takeshi fell backwards, and the impact sent waves of pain up and down his spine. He coughed and tried to breathe again as he attempted to sit back up. A foot harshly found its mark once more, and pinned him to the rough ground without mercy.

"You bastard!" His assailant growled. "You almost ruined this job and I already paid you that much! Were you seriously planning to just run away?!"

Takeshi shuddered in response. The sole of the running shoe that pressed down on him dug harshly into his aching chest. It was going to leave a bruise for sure. He tried to squirm free, but the girl merely leaned in further and added to the crushing sensation. He moaned in pain and squeezed his eyes closed.

"This is why I friggin' hate hiring incompetent goons like you!" He heard the girl complain. "I always have to clean up the mess afterwards!"

Takeshi opened his eyes and glared up at the dark silhouette of his tormentor.

"Get off me, you crazy bitch!" He managed to snarl out.

"Heh, can you get me off?" The girl replied snidely.

The innuendo wasn't lost on him. A smirk played on her lips, full of arrogance that was typical of a high-levelled esper. Indeed, he knew she was no ordinary person, and he was in a lot of trouble right now.

She continued to talk in an amused voice that rang sharply in his ears.

"You could try blowing me up a few more times, yeah? If you actually succeed, maybe it'll even feel fucking fantastic."

Takeshi scowled at her as fiercely as he could. He struggled against her humiliating hold, but knew it was futile. She was taunting him because she knew he no longer had the energy to use his detonating powers. He had expended too much today, in the job that had ultimately gotten his younger brother caught.

"I guess that's too much to ask though," the girl said regretfully. "With the way you are right now..."

She suddenly grabbed a fistful of his blonde hair, and brought his face close to hers as she crouched down. He stared into her brown eyes that gleamed like twin blades in the darkness of the alleyway. She was a wild creature, yet exceedingly beautiful; there was no denying it. His crotch swelled much to his chagrin.

"If you don't like the outcomes," he found himself snapping at her to hide his arousal, "then do the shitty work yourself!"

"Not my fault, is it?" She rolled her eyes, unfazed by his outburst. "The old man won't let me do anything other than be his plaything. It's a total pain in the ass, but I did make the deal with him so I have to keep my end of the bargain as long as he continues to keep his."

None of that made much sense to him, but he figured it was probably another one of her insane ramblings. He shuddered as she caressed his cheek lightly with her other hand. That snide smile still lingered on her lips.

"Why… Why did you want those facilities destroyed anyway?"

Her smile immediately faded at his question, replaced by an annoyed look.

"That's none of your business. I just need stuff destroyed, no questions asked." Her fine brows furrowed. The edges of her eyes hardened into a fearsome glare and the sheer intensity of it sent another ripple of undeniable lust through him. He exhaled quietly through his nose. He had to control himself.

"This time was an absolute disaster from the two of you," she said harshly. "Your troublesome little brother just had to get himself caught, didn't he?"

Takeshi gritted his teeth. Words stuck in his throat, and rendered him unable to defend himself. Even if he could, it was obvious what would happen. There was no point fighting against this girl. It was simply a trap to make him challenge her so she could create more excuses to further cause him pain. Not that she needed a reason; he suffered because of her anyway.

The girl huffed and suddenly let him go, pushing him back roughly to the ground. She stood up to her full height, and looked down her nose at him with a bored expression. Blood thundered in Takeshi's ears. His entire body ached terribly. He had burns from the large explosions he had created earlier, and harboured bruises from the rough treatment this monster had dished out. She had caught up to him too fast after he only narrowly managed to escape being discovered by Anti-Skill. He wondered where Mitsuo was right now. Was he hurt after what had happened in the facility? What would Judgement and Anti-Skill do to him? Would he be tortured for information? He had no idea what happened to those who were captured by such people. If he knew where his younger brother was, he would go and bust him out…

"Still," the girl interrupted his desperate thoughts and brought him back to reality, "I guess I can't really blame you guys completely. The facility did get destroyed after all, so the main objective was carried out with success."

Relief flooded through him at those words. Takeshi only hoped her future actions would match them.

"Besides…" The girl turned her head to gaze at something he could not see. "She's always been good at her job… that Kouhai of mine."

A small quirk of her lips turned into a lopsided smile.

"You know that teleporter Judgement girl?" Takeshi ground out. He pushed himself into a sitting position and wiped the blood from his lips.

"Hmm… Once upon a time," she replied in a vague manner. Takeshi was surprised to see a genuine nostalgia in her expression, as if she was remembering something precious long gone and lost.

Of course, Takeshi suddenly realised, anyone who was part of Academy City's darkness had their share of unfortunate events to tell. It was probably the same for this warped girl, no matter how crazy she appeared.

She craned her neck to face him again. Her eyes had regained their hard edge and he stiffened under their sharp scrutiny. He felt cold sweat run down the side of his face and drip off his chin.

"I'm letting you live because I think you'll have more uses. Keep your mouth shut as always, got it? I'll keep adding to your money stash as long as you do as you're told."

When he nodded, she flashed him a cheerless grin and turned to leave.

"Wait," Takeshi called out, "what about Mitsuo?! Do you know where Anti-Skill took him?"

She gave him a disapproving frown. "Don't do anything stupid, Takeshi-kun. I was just about to go take care of that myself."

His chest grew cold at her words. "What are you gonna do?!"

Takeshi had met this girl a numerous times over the past month now, and he most definitely could not trust her to make any decisions about his brother. Every time they met, she had shown him her cruel and unpredictable side, which often lead to indescribable torture sessions. Each meeting made him wish he had never gotten into this job in the first place, despite the excellent pay that kept them alive. Her sadistic nature and her desire for destruction were simply unreal.

"I'll do what I see fit," she spat at him coldly. She leaned in close to him again, grabbing the collar of his shirt in an iron grip so he could not pull away. He tried to stand his ground and glared at her with as much spite as he could summon. Her brown eyes gazed back at his rebellious expression with scorn, and she sneered.

"You know you can't do shit against me, so don't even try."

Takeshi wordlessly stared into her smouldering eyes. The small patches of hope he had mustered shattered, because he knew that she was right. He was just a pawn in this dark game. She was a Level 5 and he was a Level 4. Despite the similarity in numbers, their power levels were vastly different. There was simply no way he could win against her in an actual fair fight.

"Don't worry." She finally let him go and straightened up. "I'll look after your brother."

As he shivered, her eyes ran down the length of his body, and took in his sorry appearance. A sudden smirk turned her mouth upwards.

"Ohh, what's this?" She grinded a heel cruelly against his bulging crotch. Takeshi hissed.

The monster laughed, pulling her foot away.

"Sorry, sorry~ And here I thought you were in pain, when you were actually just enjoying yourself."

Takeshi felt his face glow red and become heated. The girl chortled at his obvious shame. Her amused grin grew wider.

"Good luck taking care of that load," she said casually. With a loud laugh, she waved and turned her back on him. "Don't worry about anything. I'll make sure to give your little brother a good time too."

With that he was alone, the laughter of the monster ringing in his ears as his painful erection burned and begged for release.