This story is a prequel to Zen Garden, but should be read after.

Disclaimer: I do not own Yuyu Hakusho. Of course.

I growled in frustration, resisting the urge to slam my fist into the rock ledge I was perched on. How the hell was I supposed to find this demon going on nothing but appearance? I was a tracker demon, for crying out loud! I could only locate my targets through the scent of their blood. Maybe the Boss was testing me? Yeah, that had to be it. Even though I was one of the oldest assassins in the whole damn Requiem! I didn't need anymore trials to prove my worth. Damn it!

Sighing, I pulled out the brief profile on the demon. It wasn't very descriptive. Short guy, black spiky hair, red eyes. Not even a picture. Oh well. He better not blame me if I took more time than he wanted to finish this mission…

I jumped off the ledge and my feet slammed into the side of the mountain. The rocky surface gave away, and I fell backwards, sliding down until at last I landed on solid ground. I collapsed instantly as a spasm of pain shot through my scratched-up legs.

"Not my smartest idea…" I mumbled, forcing myself back to my feet. If I remembered correctly, there was a small pool nearby. If I washed my legs in there, hopefully I'd still be okay to complete the mission.

I gasped slightly as the icy water hit my injured legs. Moments later the pain numbed and I relaxed until all the blood had washed away. I leaned back, enjoying the feeling.

That is, until I felt something move in the water.

I jerked my legs out of the pool just in time to avoid the sharp teeth of a Streamwater beast. Several others were milling about the surface, attracted to the blood I'd washed off in the water. I began to panic slightly. These things could move just as well on earth as they could water, and they were impossible to kill unless fire was used. But I didn't have any fire tricks on me at the moment, did I?

One of the beasts began to crawl out of the water towards me. I shuddered involuntarily.

It was…just plain freaky. Its grey body was skinny and worm-like, yet its head was massive and bubbly, with its mouth taking up most of the space. Its eyes were a sickly white, with no irises or pupils or anything. It had short legs that it was using to move up the shore to me at a speed that should not be capable of its bodily physique. And don't even ask me how it managed to keep that head up with that tiny neck. I stumbled back again, thrusting my hand into my pouch around my waist and searching frantically for something to help me.

Other Streamwater beasts were crawling out of the water now. The leader was the biggest and most disgusting of them all, and it was the one that charged first. I swore and yanked my hand out of my pouch so I could throw up a shield - the only one of my tricks that I myself could summon without the help of a talisman or the like. The beast hit the shield and shattered it, but was thrown back into its fellows. But they hardly noticed they kept crawling towards me, like some twisted army.

With my injured legs, it'd be impossible to outrun them. Was this it? Was I going to die an inglorious death at the fins of a bunch of fish?

"What the hell are you doing, you numbskull?" A deep voice shouted behind me. Bright orange flames roared down to the beasts, roasting a couple and sending the rest scurrying for their lives back into the pond. I gaped, unable to believe I had just been saved.

"Were you just going to let them eat you? If you're that interested in dying, I'm sure there are easier ways." My savior said irritably, approaching me. I turned to look at him with a grateful smile.

"Thank y-" I froze in the middle of my sentence. Short…spiky black hair…Red eyes…This guy was my target!

My instincts took over before my mind could catch up. I kicked out his legs and slammed him to the ground before straddling his waist and shoving one of my knives against his throat.

"What..!" He exclaimed before I pushed in the knife just deep enough to draw a thin line of blood. That shut him up right quick.

"Sorry," I said quietly. "It's nothing personal, Mr Shiguke. Just my job."

"Shi-Shiguke?" He choked. "I'm not Shiguke! My name is Hiei, you bitch!"

I paused. "What?"

Shiguke/Hiei took the distraction to throw me off. I stumbled backwards, and my wounded legs forced me to lose balance. I smacked my back hard against the rocky ground and before I could get up again, Shiguke/Hiei had slammed his foot onto my throat. I saw stars.

"You evil wench!" He snarled angrily, grinding his foot into my throat. "I should just kill you now!"

"Then do…it," I growled as best as I could while my mouth began to fill with my own blood. "Come on. You have the balls, don't you?"

Hiei scoffed and took his foot away. I inhaled glorious air and sat up. "I'm not so pathetic that I have to kill a weak demon begging for death."

I got shakily to my feet. "Take that back."

Hiei seemed unfazed. And I had to admit I probably couldn't do much damage to him as I was right now.

"Who are you?" Hiei asked. "I think I have the right to know, since you just tried to kill me."

I growled low in my throat. "The name's Zen. I'm roughly 147 years old. Blood type B. What else do you want to know?"

"Why did you try to kill me? And especially why did you mistake me for this Shiguke guy?"

I gritted my teeth. Man, this was humiliating. "Shiguke is my next target. I'm to murder him. I was only given a description of his appearance. And unfortunately for us both, you match the description perfectly."

"I know that demon," Hiei said almost instantly. "He's been causing trouble around here lately. Didn't know his name though. Is that why you've been sent to kill him?"

I shrugged. "Maybe. I don't know. When you've been at my gig for as long as I have, you learn not to ask questions."

Hiei snorted in disdain. "This demon…Shiguke, did you say? He's been pissing me off. Since it's obvious you can't do it by yourself," - insert impudent sneer - "I'll help you take him down."

"Thanks a lot," I said sarcastically. "But if it's your help or nothing, I'll go with the 'nothing' option."

Hiei frowned at me, and I really didn't like that smug expression he was wearing. "Have you forgotten something? I did just save your life, after all."

I gritted my teeth in anger. He was right. According to ancient laws, that would put me in his debt.

"I'll release you from your debt to me when we kill Shiguke. You should be honored. I'm rarely this nice."

I burst into laughter. "You call that nice? All you've been doing is insult me. And now I can barely breathe, thanks to you. You're an ass, but…" It was killing me to do this. "I do need your help."

Oh damn. It should be against the law to look that smug. I got slowly to my feet.

"How do you expect us to find him?" I said evenly.

"I have a few friendly sources," Hiei said casually. I glared at him. He was getting more irritating by the minute. Why couldn't he have been Shiguke after all…? Then I could have just killed him and been done with it.

Hiei's sources turned out to be a couple of low-level demons who were good at keeping their ears to the ground. And I'm pretty sure they didn't consider themselves 'friendly sources' to Hiei. I had to admire his style, though. Hiei was a master when it came to threatening/torturing demons to information. I certainly had newfound respect for him. If he ever had any interest, he could make a good assassin. But I don't think he swung that way. Still, I was getting to the point where I kinda liked him. I'm sure we'd never become bosom buddies, but maybe friends wouldn't be too much to hope for.

"Come on," Hiei called to me, no longer sounding too happy at his offer to help me. "They said Shiguke should be camping out near Deathcall Rock on the edge of Yomi's territory. Since he's ambushing anyone who comes near, he should be relatively easy to find."

"Right," I said. I leapt off the boulder I'd been perched on and began to walk in the direction of Deathcall Rock. Assuming there were no interruptions, it would take about half a day. Hiei left his 'friendly sources' bleeding on the ground and fell into step beside me.

"If you require help on a mission like this," Hiei said carelessly, "doesn't that mean you kind of suck at your job?"

I gritted my teeth in anger. Did I just say I liked him? I meant hate.

"Every assassin has their specialty that makes them good at what they do. If they didn't, they wouldn't live that long. I have an extremely useful skill, but if I don't receive a certain condition, I can't use it. I've been doing this for almost my whole life. Believe me, I'm one of the best assassins out there."

Hiei didn't seem convinced. "I don't suppose you'd want to tell me your 'special skill?'"

I glared at him. "I don't feel particularly inclined to do so at the moment."

Hiei gave a small chuckle. I frowned at him. He was an enigma, that was for sure. He'd save my life, I'd tried to kill him (on accident, of course), he'd offered to help me, and now we were out to kill my target together. People like Hiei were never moved to action unless there was something they could gain by doing so. So what was it for him? I wanted to know, but I didn't dare ask.

"There it is," Hiei said softly that night. I studied the large, oblong stone that stood out in the middle of the plains. It didn't look particularly intimidating, but bad things had a funny way of happening around Deathcall Rock.

I resisted the urge to double over to relieve some of the pressure on my scratched up legs. I was not going to show any more weakness to Hiei. But apparently he noticed something because he glanced over at me and snorted in disgust. I was on the verge of retorting when he actually shoved me hard enough that I fell, landing on my butt and probably breaking my tailbone as well. Thanks, you midget asshole.

"You're unbelievable," he said in a way that made it clear that it wasn't a compliment. I scowled, but unfortunately could not think of a retort. Man, it was really killing me to keep letting him win like this.

I inhaled sharply as Hiei roughly pushed up my leather pants to my knee. As I watched in surprise, he tore off a section of his cloak and began to tend to my legs. While he wrapped the cloth around my legs, he grumbled to himself.

"What kind of idiot assassin lets themselves get hurt so badly? How the hell did you live to even hit puberty?" He slowly raked his eyes up and down my torso. "Not that you ever actually did reach it."

"Hey!" I snapped furiously, attempting to get back to my feet. Hiei ruthlessly slammed his hands against my legs, completely incapacitating me for the moment. When I stopped struggling, he slowly let go of me and resumed his work with the makeshift bandage. I was fuming, but I kept it to myself this time.

"There," he said at last, welding the end of the cloth down and standing back to admire his handiwork. I got slowly to my feet. Well, fancy that. No more pain.

"Thanks," I said grudgingly. There was that smug look again.

"Well, hello," a new, scratchy voice cajoled. Hiei swept to his feet and I scrambled after him.

Another short, spiky black-haired, red-eyed demon was standing on the top of Deathcall Rock. I figured he must be related to Hiei, because he also had that whole 'I'm a total badass and we all know it' look on his face. But I had to say, Hiei was far better looking than Shiguke. It must've been the lack of warts.

"You're Shiguke?" Hiei asked calmly, stepping in front of me almost like he wanted to protect me. But I didn't believe that.

That must've been the last thing Shiguke had been expecting. His jaw almost literally dropped to the surface of the rock and he just stood there, gaping at us. A moment later he regained his composure and crossed his arms over his chest.

"And how exactly do you know of me?" He asked measurably. I reached discreetly down to grasp the hilt of one of my daggers. But Hiei remained completely calm.

"We're here to kill-"

I gasped in horror and let go of my dagger so I could smack my hand across Hiei's mouth to muffle the rest of the sentence. With a ferocious growl, Hiei tore my hand away.

"What the hell are you doing?" He snarled in my face. I stood my ground.

"You idiot!" I snapped, taking a handful of the front of his cloak and yanking him down so he was eyelevel. "Never tell a target that you're going to kill them!"

He shrugged, acting very unconcerned. "It doesn't matter whether he knows or not. He's laughably weak. There's no way he'd be able to escape from me even if he wanted."

I scoffed and let him go. I had to keep reminding myself that the only thing that really mattered was taking out Shiguke. Hiei and all the annoyances he caused were just collateral damage.

And surprise, surprise - Shiguke had skedaddled while Hiei and I had been busy arguing. And since I'd never gotten a good whiff of his blood, I couldn't track him. But that didn't seem to be a problem for Hiei.

"Come on, already," he said to me. "He went this way."

Was I really that bad at the art of assassination? The more time I spent with Hiei the more I began to doubt myself.

It rapidly became pitch black night as we pursued Shiguke. And I finally became more useful than Hiei. I could see perfectly fine in the dark, but he couldn't. He directed me to follow Shiguke's aura trail while he held on to my belt and I kept him from tripping over something.

"He's stopped," Hiei finally said when we had reached a forest. He let go of me almost immediately. He must really hate having to depend on others. He began to lead the way instead, at a much slower pace than when I'd been leading. I was faintly amused, but decided to go along with it. Might as well humor that whole male-dominance thing.

I saw him first, of course. He wasn't hiding or anything. Probably got pretty confident that we'd never be able to find him. I slipped one of my daggers out and prepared to creep forward. Hiei grabbed my arm and yanked me aside, so that we were hidden behind a tree. He trapped me against the tree trunk with his own body. Against my will, my heart leapt in my chest.

"Don't," he breathed in my ear. "He's far too strong for you. You'll get killed. I'll take care of it."

I wanted to protest, to prove him wrong, but deep in my heart I knew he was right. I slid down the tree trunk until I came to a rest at the base of the tree. Hiei slipped out towards Shiguke without a glance at me. I felt like dying on the spot.

I heard the sounds of a fight going on, and two different scents floated over to me: one that smelt like rotting vegetables, and the other like burning wood and charcoal. The latter had to be the scent of Hiei's blood, so the former must belong to Shiguke. They were both injured.

Suddenly, the scent of Hiei's blood saturated the air, meaning he'd suddenly been seriously wounded.

I couldn't stop myself. I leapt out from behind the tree, digging in my pouch for some sort of trick to help. My hand closed around a small glass splinter, and I yanked it out of my pouch in triumph. I rested it on the palm of my hand, infusing it with some of my energy. It began to glow a soft white and the temperature around it began to drop rapidly.

"Hiei, move!" I shouted. He glanced back at me and his red eyes widened in surprise to see the glowing white miniature spear in my hand. He smartly dodged out of the way, leaving Shiguke open. I blew on the spear.

It multiplied at once, sending about a hundred of the formerly glass (they had turned into ice) shards speeding in his direction. He was too slow to move and was impaled by the shards. They punched right through is body, vanishing once they reached the air on the other side. Blood sprayed everywhere and I crinkled my nose in disgust as the scent of rotting vegetables permeated the air. Shiguke gaped in shock before falling to his knees. A moment later, he collapsed completely. I breathed a sigh of relief that I'd managed to accomplish the job. Hiei approached me.

"Perhaps you do have a bit more talent than I give you credit for," he said nobly. I didn't reply. It wasn't really my talent since the ice shards trick didn't even belong to me, technically.

I walked over to Shiguke's body and knelt next to him. I rested my hand on his perforated back, sensing out his skills. Huh. He could summon force fields, which were stronger than the shields I could already produce. That would come in handy. I exerted a bit of my energy and absorbed his ability. It didn't manifest itself into a physical representation, like the ice attack had, but instead adapted itself into an actual power of mine. Which was easier to summon but would cost me a lot more energy. I sighed and stepped back. Hiei didn't question what I had done but instead set fire to Shiguke's body. In seconds it had been reduced to a pile of foul-smelling ash.

"Now what?" I said wearily. All I wanted to do was go back to the Requiem and take a nice long rest…

"Now we go back to being enemies." Hiei replied harshly. "I may have helped you this time, but believe me, we never were and never will be allies. Next time I see you, I will kill you."

I blinked in surprise. I honestly hadn't expected him to say that. I set my jaw in determination. "Fine," I said coolly. "I'll grow stronger than you in the meantime. That way when we do meet again, you won't have a chance of killing me."

Hiei snorted. "Good luck with that. You'll need it."

I turned away from him with a scowl and sprinted off. I didn't know whether I actually wanted to ever see him again or not.

I walked down the stone halls of the Requiem headquarters, consumed in my thoughts. I did want to meet Hiei again, but I refused to be the weaker one when that time came.

"Did you accomplish your mission?" Asuka, one of the supervisors, asked me. I nodded shortly and continued on my way.

I flopped down on my bed once I reached my small chambers. I couldn't seem to get those damned red eyes out of my head…

"Just you wait, Hiei," I muttered to myself. "Just wait."

Thanks for reading! I hope you enjoyed this little insight into the enmity of Hiei and Zen's relationship. If you didn't, then please, please don't review.