A/N: So here it is, the next chapter! And look, it's even longer than the last one. I just want to say thankyou so much for all the reviews, your thoughts and views have really been a powerful motivator and I appreciate you taking the time to leave them. I hope I live up to your expectations

I've also got to apologise for the fact that there's no Dyson in this chapter (sorry!) though I did put in Vex as a consolation prize because he's so awesome. Don't worry, though, Dyson will definitely be in the next chapter. Also got to make it clear that whilst this is a Denzi fic it is gonna be very slow burn, mostly because I want to do it right. Hope you enjoy

Disclaimer: Some of the conversation is taken from the Lost Girl episodes 2x22 and 3x03.

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The overwhelming relief that washed over Kenzi at the sight of Trick returning to the land of the living was short lived. No sooner had he uttered his desperate question about the Garuda did everything begin to fall apart again. First it was just a slight sway in Bo's form, not so concerning – after all, she'd just fought an epic battle with the Big Bad of all Bads and won, she was entitled to feeling a little lightheaded. Then her eyes flashed blue – never a good sign – and Trick's alarmed voice pulled Kenzi to full alert.

"What have you done?"

"I couldn't lose you," Bo explained, shaking her head tearfully, as Kenzi gripped her arm and eyed her with concern. Her eyes were brown again. That was good right? Just a little momentary slippage, not so bad. Everything was going to be OK.

"But you could lose yourself!" Trick protested, rising up slightly in a panic. "Unbind her quickly!"

Kenzi didn't need to be told twice. "Got it." Jumping to her feet and ignoring the way her vision dappled slightly from the blood loss and sudden movement she rushed to Hale. "Siren, hand!" She didn't wait for him to comply, forcefully grabbing his appendage and pulling out a pocketed knife. Hastily, she cut the skin of Hale's palm and pressed her own on top of it. There was no need to carve up her own flesh – she had enough of her blood outside her body already to break several binding spells.

Bo was on her feet now, too, in full blue mode and looking unsettlingly pekish. "My strength is unmatched. I will reign as queen and you shall all tremble before my power." There was no need to wait for such an outcome, Kenzi was already shaking at the sight of her best friend so . . . gone. That was the only word she could think of to describe it. Bo was just gone. There was no sign of her in the glowing cobalt eyes, the powerful pose or the ravenous expression.

"Quickly before the darkness overwhelms her completely!" Trick interrupted, bringing her back to the present.

Kenzi inwardly cursed herself for having hesitated. "With harm to none, thy will be done, thou cannot harm them, Bo," she gasped. Eyes wide she watched, waited for the blue to disappear and for Bo to return to them, to her.

She waited.

Come on, Bo. Please.

The knife which she'd returned to her pocket dug into the skin of her thigh, unbearably there. She hadn't just packed it for the unbinding spell. It had another, darker purpose, one that she'd done her best not to contemplate when she'd shoved it into her pocket earlier that day. If she had, even for a second, she would have torn it from its place and thrown it out a window in a heartbeat. If she thought about what Bo had asked her to do, had her promise to do, she would never be able to go through with it.

Only, now she had to think about it. Bo's eyes weren't changing, the blue wasn't going and Kenzi could hear the timer in the background, racing down.

A second's pause.

Please, Bo.

The succubus snapped around to glare at her, the warmth she usually held for her best friend now an ice that pierced Kenzi's heart. "You dare try to stop me, mortal? I, the all-powerful, the future queen? You will pay for your foolish mistake. I will rip the life from your body until there is nothing left and then return it to you before taking it once more! I will bring you back again and again, kill you over and over, so that you may know the agony of death a thousand times over! You will never know peace!"

Kenzi shook. Not because of the words, of the terrible fate being spelled out for her in horrific detail, but because it was Bo saying it to her – Bo: her best friend, her sister.

"We're too late," Trick sighed, voice falling with dismay and realised despair.

She shook her head. No. No.

In that instant, Bo attacked.

There was a flurry of movement as the succubus came at her and she could only blink, stunned, as the man beside her flung himself in the way. If Bo was disappointed at her change of prey, though, she didn't show it. Instead, her arm shot out and she gripped the siren around the throat, eyes glowing ever brighter as she opened her mouth.

Kenzi had seen Bo feed before and there was usually a certain length of time you could rely upon from first taste to death, time in which to intervene. That didn't exist now, though. Hale's chi, light and beautiful, flew through the air into her open mouth, hovering between the two of them for only a second before disappearing into her completely.

He dropped to the ground, lifeless.

A cry of dismay sounded. It took Kenzi a moment to realize it was her own.

And then everything was chaos.

Dyson, angered by the loss of his friend, moved to attack – to subdue, Kenzi internally corrected herself, for even now she knew the wolf would never be able to bring himself to kill the succubus – and Bo swung around, seemingly delighted at the prospect of a new opponent. She didn't even need to touch her victim this time to do damage, getting close to them no longer seemed a requirement. Her mouth, still open and hungry, breathed in and Dyson's own mouth was yanked open as he stopped in his tracks. The chi flew out of him.

Kenzi tried to move, to act, but her limbs stayed frozen and immobile. She had to do something, to stop this. Dyson's life was bleeding out of him and Hale was-

She had to do something.

The knife burned unnaturally hot in her back pocket.

No, not that. Never that.

Dyson collapsed to the floor. He didn't move.

Vex took that as his cue to leave and hastily raced to the exit. Bo wouldn't let him go, though. Her hunger, far from being satisfied by her recent snacks, was now only whetted and she thirsted for more. The Mesmer was only to reach the door before he too was stopped in his tracks by the succubus's powers.

He fell faster than Dyson.

The knife-

No.

Trick was on his feet now, hands up, trying to calm his granddaughter, to reason with her. It was no use. Kenzi closed her eyes, unable to watch as he too met his fate. It was so unforgivably weak of her but she couldn't open her eyes. She couldn't act. She couldn't do anything.

She had promised Bo and she couldn't.

Lauren was next and the doctor, a mere human like Kenzi, died even quicker than the rest.

Then there was only her. The weak spot, the liability . . . the one with the means to stop this but who had failed.

'You are the only one I can trust with this.'

She deserved what came next, she even wanted it.

'You are my best friend.'

But she couldn't accept it.

'Promise me.'

Just as Bo was almost on her, Kenzi withdrew the knife from her pocket and pounced. Breath hard, side aching and still slightly delirious from blood loss, she tackled the taller woman to the ground. There was a gasp beneath her and Kenzi's hands trembled around the hilt of the knife where it had penetrated her best friend's heart.

It wasn't that easy, though.

The succubus struggled beneath her, writhing and Kenzi knew she had to act quickly because her weight wouldn't be enough to hold her down for long. On the streets, she'd been witness to the fact that a stab wound to the heart was usually always fatal but not always instantaneous. Depending on where it went in and what was damaged a person could stick around for quite a while.

With Bo, that wasn't an option. She would use that time to feed off Kenzi, to heal.

There would be no one left to stop her then.

To keep the promise.

Quickly, Kenzi tore the knife out of Bo's heart and flung it as far away from the two of them as she could – far enough that it wouldn't be a possible weapon for Bo's reaching arms. The action caused further damage and Bo screamed, eliciting a wince from the human. She couldn't hesitate, though. Not again.

Using one hand to wrap around the succubus' weakening but still flailing ones and hold them down against her chest, she slammed the other over her mouth. Staring into blue eyes, she struggled to hold the other woman down, making sure that her mouth didn't slip away for even a second and open. That would be the end of her. One second was all it would take to suck her chi, for this to all be over.

Kenzi nearly gave in at the thought.

'Promise me!'

Shaking her head, she kept her grip firm.

Hot blood, thick and sticky, swamped the hand she was using to restrain the other woman's arms over her chest. It slithered between her fingers, making Bo's skin slippery beneath her own and nearly giving her the chance to break free a couple of times. Biting her lip, she held firm, trying to ignore the blood.

Ever so slowly, the struggle lessened as the woman beneath her weakened. Kenzi stared into Bo's face as it grew ever paler, her features slackening slightly with every passing second. Eventually, even the blue began to fade until there was nothing but brown in those familiar depths again.

'I promise.'

It was in that instant that Kenzi saw it: recognition. For a second, the monster was gone and it was just Bo, her Bo, staring up at in her in shock and pain and love.

"Bo?" her voice cracked.

Any and all movement beneath her suddenly ceased. The blood stopped pulsing, the chest stopped shuttering with desperate breaths, and Bo's eyes became still, the blue gone, the light gone, everything gone.

"Bo!" she cried, tearing her hands away and cupping the woman's face, branding crimson to her cheeks. "Bo, please! I'm sorry, Bo, please! Please come back! I'm sorry! I'm so sorry. I'm sorry, please, I'm…." The pleas faded away into incoherent sobs as she gripped her friends face, shaking her, begging her.

It was useless and the realization was shattering.

Letting out a wail, she bowed her head to Bo's chest, burying it in the heat of skin and blood. Closing her eyes, she prayed for her to come back, for them all to come back.

Please. Please. Please.

Tears melding with blood, she waited, alone.

A gasp tore itself from Kenzi's lips as her eyes snapped open. For a moment, she couldn't place the darkness of the room around her, the lack of wet warmth from the blood, the lack of Bo. Tearing into a sitting position, she looked around, searching, trying to make sense. "Bo?" she croaked, dry eyes beginning to water.

Then, slowly, the darkness became more recognisable to her gaze, shadows shifting and forming into familiar objects: a dresser, a closet, her teddy bear, Ziggy, in the corner . . . a bed, which she was sitting on, tangled in blankets.

It was her room. She was in her room.

She'd been asleep.

She hadn't been back in the former mental asylum where they'd fought the Garuda – that was all far away. She hadn't just watched all her friends die, powerless to do anything. She hadn't just killed Bo.

It was only a dream – a nightmare.

She could still feel Bo's body beneath her own, though, dead. She could still hear her screams, feel her blood.

She still felt like she'd failed.

Crawling out of bed, heart beating frantically in her chest even though she'd only just awoken from sleep, she raced down the stairs from her room. Bo's was on the level below and Kenzi nearly tripped down the last few steps in her blind haste. Breath coming in short gasps, she sprinted to Bo's room.

She needed to check, to see. She needed to make sure that the blood on her hands wasn't real.

She halted at the double glass doors to Bo's room, left closed as they had been ever since Vex moved in – neither woman trusted the former Mesmer not do terrible things to them in their sleep, like draw dicks all over their faces. The succubus was sleeping soundly in her bed, snoring loudly with the blankets flung half off her.

She was alive. She was safe.

She wasn't gone.

The relief was so strong, Kenzi nearly collapsed to the ground under the weight of it. As it was, she allowed herself to slide slowly to the floor and lean back up against the wall. Closing her eyes, she worked to steady her breathing.

The nightmares were getting worse. Every night for weeks, they'd been plaguing her, each one harder to brush off than the last. This wasn't the first she'd had about their final showdown with the Garuda but it was certainly the most horrific. In the past, the nightmares had always been shorter. She'd only lose one friend or maybe two to the darkness inside Bo. Each time, she'd wake with a horrible feeling in her chest, mourning losses that hadn't really happened.

The first time Hale had died, she'd done her best to track him down the next day, to schedule away some quality Sidekick Pals for Life time but he'd been too busy with Ash duties. She'd gotten a glimpse of him, a brief fist bump and then he was off. She'd been left behind, a sick feeling in her stomach.

When Dyson had died, she'd made her way to the police station first thing the following morning – bright and early, which had drawn raised eyebrows from Bo. She'd spent the day practically stalking him, something that had probably been irritating to the detective, though he never gave any indication of the fact. She'd needed to reassure herself that she hadn't lost him.

She'd never had to kill Bo before, though. She'd always woken before that point.

Until tonight.

Letting out a shaky breath, she continued to try to calm herself and stay quiet. Vex was in the room, sleeping in a heap on the couch with his eye-mask on. She couldn't afford to wake him, to risk his questions or the chance that he might tell Bo.

She didn't want her best friend to know about this.

It was so stupid.

They risked their lives daily and yet she couldn't even handle a few bad dreams in the night? She was made of tougher shit than that.

Yet every night since the nightmares had started, she'd woken abruptly, shaking, too scared to go back to sleep and risk falling into another dream. They weren't all about the Garuda, some of them didn't even have anything to do with Bo and her friends, but there were none of them that she could stand the thought of revisiting.

She hated it but even more so she was tired of it. She was so tired. She didn't know how many more nights of half-sleep she could take before she collapsed. She was a girl used to sleeping her day away, after all, and therefore getting plenty of zzzs. There was only so much coffee one could consume, as well. Already she was starting to get the shakes from caffeine overdose during the day.

Maybe she should just sleep.

The nightmares were horrible but she could tolerate them. She should tolerate them. What if she was on a case with Bo and they got into trouble and Kenzi was too weak to help? What if she got Bo hurt?

She had to sleep.

Closing her eyes, Kenzi breathed out deeply through her nose, trying to relax.

An image flashed in her mind of Bo's pale, lifeless face, staring emptily into her eyes.

Kenzi kept her eyes open after that.

The skin beneath her left sleeve itched and burned. It was a constant but welcome ache to keep her from falling into the trap of sleep through the rest of the night.

Kenzi tried not to question things too much when Bo jumped from searching for her AWOL phone, to her and Vex being cute little make-up buddies (which was so true), to bemoaning the fact that she was make-up buddy-less herself, to pouting about Tamsin being too Mean Girl to be her friend, to wanting to have a 'private' talk with Dyson (which, Kenzi had a feeling that, while private parts would certainly be involved there wasn't likely to be much talking going on). When you were BFFs with Bo, you just sort of had to take these things in stride. Maybe she was just scatterbrained today, maybe she'd OD'd with her succu-loving and was now on an energy high or something, or maybe she was just possessed. Really, it was all part in parcel. Just go with the flow was what Kenzi'd learnt, just go with the flow.

Watching her bestie walk out of the shack with a bouncy yet purposeful stride, Kenzi thought over her parting words. So, she was going to go talk to Dyson. About what, she couldn't be exactly sure, but she had her suspicions. Their on-again, off-again sexy-times were bound to come up. Maybe Bo had finally come to her senses and realised that, whilst the doc was OK and all, it was the wolf that truly deserved her. The guy had sacrificed his freakin' love for her, after all!

Kenzi trusted Dyson with Bo, she knew that he would do anything for her and that he certainly wasn't going to screw her just because the Ash told him to – which, really? Talk about an employer over stepping. That was just icky.

He was a good guy. He would be good to Bo.

And he deserved to be happy. She wanted him to be happy. She wanted Bo to be happy. If that meant the two of them being together then she'd sooner push the two's naughty bits together (ew, OK, gross visual) than march in the Lauren pride parade.

Nodding to herself, Kenzi returned her attention to Vex, trying to ignore the sickening feeling in her stomach. It was the same one that always writhed within her when she thought of Bo and Dyson together. It was one she'd grown used to, though. She'd had to.

She'd made herself.

"Private," she mused, allowing a smirk. "Lauren's pelt is going to be steamed!" she sang, complete with an operatic gesture of the arms. Petty or not, a small part of her delighted in such a fate for the doc – the woman so needed to get knocked off her pedestal a bit.

Vex didn't look nearly as gleeful. "What's it with you and the doc? I mean, besides the terrible bedside manner and the fact that she's a damn sight cleverer than you?" Ouch. Kenzi tried not to let that last part sting.

So the doc was better schooled than she was. Kenzi had had other things to occupy her time other than getting a fancy medical degree – like just staying alive, for instance. Finding food, shelter and money had been her priorities and she'd been pretty damn good at it, too. Just because she wasn't book smart didn't mean she wasn't clever. She'd like to see the doctor work her way out of handcuffs in less than five minutes.

"Not to mention sneaky," Kenzi added pointedly. "She spy-banged Bo." Something that it seemed only she could remember. Bo might have forgiven her for that but it had shown Kenzi a side of Lauren that she wouldn't soon forget. She'd been willing to lie and betray Bo to serve her own ends and that wasn't just a momentary slip of the conscience, stuff like that never was. It was an indicator of a kind of moral compass that would always make you untrustworthy to a degree. She'd met people like that and more than a few had screwed her over.

No matter how far Lauren Lewis had come, in Kenzi's mind that made her a danger to Bo.

Vex, however, remained unconvinced. Not to be unexpected from someone that deceit and betrayal probably came as natural as breathing. "Dyson's drop-kicked Bo's heart ten times over and you still howl when he comes round."

Kenzi's mouth dropped open, affronted. "I . . . No!" That wasn't it at all.

Flustered, she swept to her feet, turned away, paced.

It wasn't true. She supported Dyson because he was good, good for Bo. Sure he had hurt her but . . .

Well, she knew why he had hurt her. She understood.

Lauren she didn't know at all, didn't understand.

Dyson, as much as he may have hurt Bo, she knew would never actually be a threat to Bo. Lauren on the other hand . . . well, what did they really know about Lauren?

That sick feeling in her stomach nibbled at her defences, though, hinting at something more. It said that maybe the reason she was so supportive of Team Dyson for Victory Bo had nothing to with Bo at all, or Lauren. The reason was Dyson himself.

That wasn't something she was willing to mull over, though. Not now and not in the future. It was a potential truth that had to stay hidden – for her sake as much as Bo's.

Exasperated, she swung back around to face Vex, hands on hips. At the moment, she kind of hated him for bringing this particular truth to the not quite surface. "Listen, are you going to teach me the double-pump-smudge-proof technique or not?"

Vex sighed, leaning over the back of the couch with a dare-she-say-it fond look on his face. "I'm so proud of you." Mercifully, he decided to drop the subject of Dyson and her maybe-howling. "Come here," he said, crooking a finger at her. Relieved smile in place, Kenzi did exactly that.

Taking a seat, she allowed herself to become a doll for him to work his make-up wonders on. Say what you would about the former Mesmer and his shady, murderous past, he was killer with a mascara brush.

….

Vex eyed the tiny spunk of a human in front of him as he worked on lathering up her eyelashes with mascara, using his oh-so-perfect bushman's technique. Occasionally, he'd offer important tips which she'd either grunt at or respond with some form of snark. His mind was still on their earlier conversation, though, as he was pretty sure hers was as well.

She may not know it, or perhaps just wouldn't admit to it, but he knew all too well why exactly she had the pom-poms out for wolf boy. In fact, it was so obvious that it was almost embarrassing, even more so because he seemed to be the only one who could see it. Really, was it not the succubus and her band of merry men that had defeated the all-powerful Garuda (not without his indispensable assistance) that he'd been hanging out with or the blind mice? They were all so painfully oblivious to everything around them. When one did, for once in a blue moon, happen to notice something than it was an end of the world kind of crisis and they quickly buried it back up again. A bloody soap opera, that's what it was – only not half as fun.

The human had the hots for the wolf! There, was that so hard? He could tell it from a mile off. Of course, he couldn't tell you why. He couldn't see the appeal in Dyson himself. The man was hot, the Mesmer would give him that, and given the chance he'd certainly take him for a night of fun down in the dungeons of his club, but his personality certainly left something to be desired. He was just so broody and boring. Really, Vex couldn't for the life of him understand what made him attractive to someone like Kenzi who, frankly, had more personality than she knew how to handle most days.

For whatever reason, though, the girl was gaga for wolf and that was her prerogative. Vex wasn't about to hound her about it. Or, well, he would, if she'd just up and admit to it already. But he supposed that would break some code of bestie conduct she had going on with that Succubus. Vex resisted the urge to roll his eyes. Honestly, these humans and their morals. If it was him, he'd just screw the wolf and be done with it. If he felt truly concerned about the succubus's feelings on the matter then he'd just invite her in on the fun.

There, problem solved.

Why did nobody ever ask his advice?

At least that way she'd get whatever naughty feelings she had out of her system and the two of them could return to talking about truly important things – like the best shade of eye shadow to make her eyes really pop and he had some ideas– and leave all these mushy puppy love feelings in the dust. Really, it just made him nauseas. He wasn't a couple's councillor for crying out loud! Although, he'd make a rather good one, don't get him wrong – have them all screwing by the end of the first day and by the end of the week? Orgies!

A hiss brought him back to the present. It was Kenzi, who had flinched out of his reach when his arm had brushed up against her left, knocking the mascara wand against her cheek and messing up her look. Vex sighed; bloody human.

"Nice one, love," he griped but she wasn't listening.

Instead, she was cringing in obvious pain and clutching at her arm. Despite himself – and he would never admit so – he was concerned. "What's up with that?" he questioned, gesturing vaguely at her arm.

Her eyes snapped to his and, for a moment, she looked alarmed. Then it passed. "Nothing." She forced a shrug. "Just a muscle cramp. Boy, can those be a bitch." Her smile was slightly wobbly and not at all convincing. She looked tired, now that he took the time to really inspect her. Make-up had covered the bags that no doubt rested beneath her eyes but the drawn look to her face couldn't be completely hidden.

Vex had been woken up by her little night time adventure last night. Honestly, was it too much to ask for a solid night's sleep? If it wasn't the bleedin' succubus shagging the chi out of her bloody girlfriend it was the human playing midnight spy on the sleeping succubus – whatever got you going, he didn't judge. He'd nearly called her on it, snapped at her for interrupting his precious beauty sleep but then he'd looked over to find her in a heap on the floor. She'd looked all too pathetic for even his sharp tongue.

Trying to block out her infuriating breathing exercises in the background, he'd rolled over and gone back to sleep.

Looking at her now, he wondered whether that was something he should bring up, along with all his other concerns. Something was clearly up with the little human, something not so nice.

But he was Vex. The Mesmer. The dark Fae. The monster of little Fae nightmares. Concerns weren't his area, they couldn't be.

So he let it be.

He couldn't afford to wonder, to care.

A/N: So, what did you think?