A/N- Somewhat late, but here's for St. Patrick's day! After all, Kurama's eyes are green! Sorry for not updating anything lately; I've been really busy at school.

Disclaimer: I don't own Yu Yu Hakusho or The Batman.

Batman's Ultimate Villain: Kurama: Ultimate Vigilante

Kurama walked steadily, his posture relaxed as he walked down a street in Gotham. It seemed odd to him that Koenma had suddenly found many things that the team needed to do in this one city. He amended that thought; Koenma wasn't sending the team on missions; they were being sent one at a time, on small, almost insignificant missions. It was odd, considering that before this, almost every mission involved saving the world once again.

Kurama was busy looking into finding a shop set up by someone. Apparently, more than one plant had displayed attributes similar to Makai plants (e.g. habits of biting, eating small rodents, eating larger creatures, and secreting acid or other harmful material). Thus, chances were high that some stray youkai was attempting to destroy humans a little at a time.

In fact, the odd thing was that none of the attacks had actually proved fatal for anything other than a few small mammals; someone had somehow tracked down several of the plants and destroyed them, but no one had found the source of the plants yet. Thus, Gotham's floral shops were locked up, and police were inside, scouring for clues or evidence that the plants had come from that shop.

Kurama passed yet another floral shop with doors closed, pausing to observe the woman speaking on her cell phone. She appeared of Asian descent, and had hard brown eyes. Her long, black hair was in a ponytail, and she wore a simple outfit, gray pants and a black shirt with a red jacket above it all. She didn't look like a typical police officer, but the gun at her side and her stance belied her to Kurama's master eyes. Thus, he approached her after she closed her cell phone.

"Pardon me, ma'am." He waited for her to turn her attention towards him, which she did quickly. "My name is Minamino—no, Shuiichi Minamino. I'm visiting from Japan, and I noticed that all of the flower shops are closed down, with police cars outside. I was just wondering: is there any danger I should be aware of?"

She paused. "I wouldn't advise buying plants at the moment, Mr. Minamino. A sort of 'super-villain' of ours seems to have hatched yet another plan to 'help the environment' with destructive plants. She calls herself Poison Ivy, and she can manipulate plants. There isn't any danger at the moment, I would say. We seem to have defeated her first attempt. Just be cautious."

Kurama smiled his famously polite smile, pretending to almost begin a bow before stopping himself. "Thank you very much, Ms…."

"Detective Ellen Yin," she introduced herself, looking at him with slight interest. She hadn't really paid much attention to his appearance, having been too deep in thought. Now she noticed that his hair was a vibrant shade of red and reached past his shoulders, and his eyes were a vibrant green. If it weren't for his faint, almost negligible accent, and his slightly angled eyes, she would say that he was lying about his origins. "You don't have much of an accent."

He smiled again, but this time, there was a hint of a shadow behind his emerald eyes. "My talent at languages is one of the things I'm proud of. Good day and thank you."

She nodded, and he walked away, pretending not to notice her continued observation until he turned the corner. Once he was around the corner, however, he frowned pensively. So, someone could control plants. Was it a youkai, or was this 'Poison Ivy' she spoke of truly a ningen? Either might be possible; Kurama hadn't really studied the reiki powers of humans, except for the ones he had to fight. He had never come across a ningen who could control plants, but that was because it took so much ki. Theoretically, he surmised it could be done.

Kurama continued to follow his nose to the scent of flowers, his quest eventually leading him to a back ally, where many had thrown out their plants in fear that they might attack. Most of the scents of these flowers were mundane, but there was one that caught his attention; an overly sweet scent. He walked to the end of the ally, standing a cautious distance away from the plant just to make sure he would be safe. The plant looked nothing like what he had seen in the makai, but also didn't look as though it would quite fit in here in the ningenkai. However, it wasn't moving, and he didn't feel like using himself as bait.

Running a hand through his hair, he picked out one of his plants, sending it forward. The other plant didn't move. Kurama frowned, ordering his plant back with his power; then his eyes widened in realization. It probably relied on heat to tell it where its enemy was. He didn't have any particular seeds that emitted heat in his hair in the moment…so….

Kurama wrapped a plant around his hand, its thick leaves acting almost like a glove. Then, he cautiously reached his hand forward. A satisfying extra weight added itself to his hand, and he grabbed it just behind its 'head,' much like one would grab a snake. He used his plant to push the teeth out of the 'glove' as he studied the plant.

It was able to move using its leaves, and to separate its roots from the ground. The blossom was indeed where the mouth could be found; it bloomed with the mouth in the center. This seemed to be a small example of the plant, as it was not nearly big enough to devour a small mammal; well, perhaps a mouse. Kurama could only assume that this plant's owner had stopped caring for it, and thus, it hadn't grown much bigger. Now, to dispose of it. Kurama paused momentarily. He didn't have Hiei's powers of fire, so the easy method was out the window. He didn't have a blender either….

He concentrated, focusing his youki on the plant, ordering it into a seed. It struggled against his will, a clear demonstration that someone else's power was in it. But Kurama was certain he could overcome that lingering power…. After five minutes' struggle, he succeeded, the flower regressing into a harmless seed. He then dropped the seed on the ground, carefully grinding it into a powder under his heel. It was a wonderful specimen, but too weak to be of any use to him. For now, it was time to see the maker of these plants.

His battle with her plant had granted him knowledge of how her ki felt; he could now confirm that it was reiki; somewhat odd, perhaps warped or forced into this form, but definitely reiki.

His pace was brisk. He wouldn't be able to find this aura without getting somewhat close; within a mile at least. He needed to scour Gotham until he found her. The police were wrong; there were still some of her plants out there, so they obviously didn't know exactly what type of flower they were looking for. She probably knew this as well, and was preparing to execute the next phase of her plan.

Kurama glanced up at the rooftops; it was true that they were close enough together that he would be able to jump them, but that would probably only put him farther away from her. If she was a true plant master, then she would be somewhere where plants were normal and expected which meant…a park or nursery. Kurama sighed. If only he was a native of this town and knew where to look….

Batman's POV

Poison Ivy was proving elusive; Batman hadn't found any trace of her in the major parks or nurseries. He was now attempting to find other minor parks that he missed in his computer. Finally, a possible match came up. It was in the center of the area that had been attacked by her plants, and no one would come to it often due to its odd location.

Batman pulled his cowl over his face, calling Robin and Batgirl to join him as he headed to the bat-mobile. He took one glance at the screen, glancing at a small window he left open. This one was tracking that thief, Hiei. Though that black hole thing he had entered had taken him out of range, Batman didn't think it was impossible that he and that black hole creating, red haired teen would come back. In fact, he felt that it was highly probable.

Kurama's POV

Kurama stiffened as he finally felt the reiki of this Poison Ivy. It was so strange a reiki that there was no doubt as to what it was. Kurama glanced around at the meager crowds before setting off at a run, despite what alarm it might cause. It was close; and it was flaring, as though in a battle rage. Kurama reached the site; Police cars had surrounded the park, though the police officers were intelligent enough not to get close, opting to be a defensive perimeter. Kurama saw the group that had fought with Hiei inside the boundary, fighting someone who was obviously the Poison Ivy he had heard of earlier; she was wearing a dress made out of plants, which was not the style of most teens.

Kurama lengthened his stride, running up the back of a police car and jumping gracefully to the ground, landing in a crouch, attracting the attention of the battlers and police easily. Kitsune just couldn't stand to stay in the shadows forever. Besides, he wanted to get the full attention of this Poison Ivy. She had similar skills to him, and he just couldn't stand to destroy it without seeing exactly what she was capable of.

"You again!" Robin exclaimed.

Kurama acted as though he hadn't heard him as he stood. "Poison Ivy, I presume?"

"And who are you?" She was defensive, but not hostile, yet. Kurama picked up a familiar scent, and surreptitiously glanced to the side. The detective from earlier was there, obviously stunned that the polite boy from earlier had jumped right into this fray.

"My name is Kurama." His eyes were still on the detective, and he noticed her eyes widen; of course, he had given her his ningen name, not his true one. "Show me what your power is, Ivy. Prove your worthiness, and I just might assist you."

The surprise was on every face. Poison Ivy's eyes narrowed. "Thanks, but I don't need your help, Kur-abra, or whatever."

Batgirl cried out a warning, spotting the plants approaching Kurama from behind. Kurama didn't show any reaction to her cry, and the plants made to attack him when they suddenly fell to the ground, disconnected from their roots. The group blinked, looking to the red headed boy once more. Now they noticed the green, thorny vine in his hands, and the feral smirk playing at his lips.

"Not good enough, Ivy. Such a weak attempt, especially if you want to fight another plant master."

Her eyes were wide. "You…you control plants too?"

Batman frowned. "But that portal…"

Kurama ignored the Batman. "Obviously."

"I don't need any assistance!" she shouted, recovering her composure. She called up more plants, and Kurama frowned. "Such a waste of reiki…no control at all. I would have thought, what with the little plant that you created, that you would have better control…"

She fumed, but did not order the plants forward. "You're one to talk, Kuraba, or whatever your name is! All you've done is summon that thorny vine! I don't think you have any talent at all!"

It might have been the setting sun, but for a moment, Kurama's eyes seemed to gleam gold to all those watching. "My name is Youko Kurama." Suddenly, there was a burst of greenery around him, and Poison Ivy moved back in fright as she beheld the large head of the plant. Kurama stepped back in front of the plant. "Don't worry. I'm in complete control."

Batman's eyes narrowed. What was Kurama's goal here? And how could the boy control greenery? All he had done last time had been to open a black hole-thing….

Kurama petted the stem of his plant, which was taller than he was, and continued talking to Poison Ivy. "You waste your reiki in controlling so many plants, and you pour too much reiki into them to begin with, due to your inexperience. You don't choose your plants wisely either; the only one I've seen actually worth the reiki poured into it was the one attacking small mammals…"

Poison Ivy glared, ignoring the Batman and the police for now. "What do you think you are, some sort of professor? And if my choice of plants is so bad, what's that and how'd you make it?"

Kurama frowned again, turning toward her. "I am a plant master, with centuries of experience. This plant is Makai Ojigi Sō; it responds to motion or heat, then crushes its victim. Obviously, as you all have heat, I'm holding it back."

Batman started at the word makai; that demon world again…and what was his goal? Was he an enemy? What did he mean, centuries of experience? Did he really want to help Poison Ivy?

"You made it?" Poison Ivy asked, seeming a bit more fearful now.

Kurama grinned at that. "Where I come from, there are a variety of plants like this. I don't bother creating a plant unless I have a specific need of it. You only deplete your ki by creating plants instead of growing them."

"Is that another reprimand, professor?" she asked, moving towards him. Obviously, she felt he was an acceptable ally now. Kurama held up a hand, and she paused. A sudden beeping made itself known in the form of Batman's batwave, and he held it up, reading the message in surprise; that thief was back….

"How nice of you to join us, Hiei. You know I can feel your presence," Kurama stated, a smirk on his lips.

A small boy appeared next to Kurama and the plant, and a shudder ran through the plant. The police looked in surprise at the boy with flame shaped black hair, red eyes, and a white bandana. "Hn. Why are you playing with them all, kitsune?"

Yin started. Yet another name for the mysterious red head…so who was he? Youko Kurama, Shuiichi Minamino, or 'Kitsune?'

"Koenma told me to investigate. Why else would I be playing with them?"

"Tch. Why don't you just finish your mission and get back to the ningen? Shiori's been calling."

Kurama frowned. "Very well then…" Suddenly, a burst of greenery erupted from underneath Poison Ivy. She struggled against it, calling up vines of her own, but had too little ki to form many plants.

"What are you doing? I thought you were my ally!" she shouted, writhing against the vines.

Kurama's face was neutral. "I lied." His plants tightened just enough to make her faint, then loosened slightly. He stepped forward.

Batman stepped between Kurama and Poison Ivy. "Who are you? Both of you."

Yin also approached, apparently forgetting that Kurama controlled plants; he had returned the makai plant to his hair as he summoned vines to hold Poison Ivy. "What are you really? And who? Shuuichi, Kurama, or Kitsune?"

Hiei smirked. "Looks like you've been talking with this one, Kitsune."

"Yes, Hiei. Detective, I am the same as you; a tantei: a detective. A Reikai Tantei."

Batman frowned. "You say you're a 'spirit world detective?'" Robin snickered; everyone knew that was impossible.

Kurama smiled, but it did not reach his eyes. "I see you know some Japanese. Yes, I do claim to be a spirit world detective."

"And what exactly does that mean?" Yin spat out; it seemed like the two teens were mocking them.

"Simple. I track down…odd…occurrences and stop them. I think this qualifies as odd."

Batgirl spoke dryly. "She's no different than you, plant master."

Hiei snickered lightly. "You have no idea how wrong you are, do you? We aren't ningen like you."

"Hiei!" Kurama warned, seemingly irritated.

Robin stared at Hiei. "What do you mean, you aren't human?"

"What do you think?" Hiei held out two hands, one filling with ice, the other with fire.

Yin's eyes widened. "Two mutations? And opposites…"

Hiei was clearly offended, his hand moving to find his sword. "Are you that foolish, onna? We were never ningen!"

Kurama sighed, wanting to place a calming hand on Hiei's shoulder, but unwilling to lose his hand. "Madam, we aren't like the super-villains you have here, even if their powers resemble ours. We come from an entirely different world."

Robin scoffed. "That Makai thing again? You're from Japan, that's all."

Kurama's eyes narrowed at the blatant disregard. "You're wrong, child. I've never been from Japan."

"Then why are all your names Japanese?" Batgirl replied scathingly.

"Because they are, onna," Hiei returned with as much venom as she had.

Yin reached for her handcuffs, hoping to arrest these two, but a voice startled her.

"Yo! 'Rama! What're you doing?" Everyone turned to where a teen with long, untamed black hair, red-brown eyes, and strange markings on his face was walking towards them. He looked somewhat roughed-up, as though he had recently been in a street fight. He pushed through the police to make his way toward Hiei and Kurama.

"Yusuke," Kurama greeted. "What are you doing here?"

Yusuke grinned. "Pacifier-breath has another mission for us; and I just finished my other one. He told me to go find you and Hiei. And Hiei, he said if you weren't with Kurama, you were violating your parole."

Hiei turned away, glaring at nothing in particular. Yusuke smirked, apparently expecting that. Kurama sighed. "Another mission, and I still haven't gone to see Shiori…"

Yin growled, drawing their attention back to her and the Batman. "I don't care what's going on, if you're vigilantes or criminals. You're still going to jail!"

Hiei sneered openly. "Just try it. Your laws aren't binding to us."

Yusuke waved a hand. "Now, now, remember me. Anyway, lady, you're seriously stupid if you think you can get these two into jail. I should know; I was the guy sent to get them when they stole something from Reikai."

Batman frowned. "You can't steal something from a place that doesn't exist."

Yusuke blinked. "How long have you been talking to them, Kurama?"

"Several minutes at least. And they've met Hiei before."

"Ah. I see why Hiei's so frustrated."

Yin growled. "Why don't you listen to reason? You keep insisting the most ridiculous things!"

Yusuke blinked, then waved a hand grandly between the two parties. "Let's analyze this for a second. On your side, there are three people dressed in capes and cowls and such, one who is wearing absolutely ridiculous colors. On our side, you have three people wearing fairly normal clothing; well, except for Hiei's cloak. But he's a slight exception. Now, just judging by appearances, who seems the most sane?"

Robin was offended, and petulantly stated, "Your hairstyles are more ridiculous!"

Yusuke blinked, then grabbed a fistful of his long hair. "Oh. I can't help it. Happens every time I access my youki. And if you think Kurama's hairstyle's ridiculous, think about what he uses it for. He stores his seeds in there, you know. I saw him take out a guy, when Kurama was bound, just by shaking his head. Amazing, you know. And Hiei…it's natural."

The party stared openly for a moment, before Batman shook his head. "You said you wanted to take them to jail, right, Detective?"

She nodded, and Batman, Robin, and Batgirl surged forward. Batman headed towards Kurama, Batgirl towards Hiei, and Robin towards Kurama.

Hiei stared, bored, before grabbing the fist that was aimed at his head. He pushed her away, and she stumbled slightly before falling. He did nothing, turning his head slightly so he wouldn't have to look at such a disgrace fully. Any good fighter would have kept his balance. She rose, lunging for him, and he blinked. His reaction was enough to grab her by the arms again, but she had managed to grab hold of his bandana. He pushed her away, not realizing this until he felt the band fluttering away from his forehead.

The fighting instantly stopped, everyone staring in shock at the newly revealed third, lavender eye on Hiei's forehead. He glared, retrieving the bandana and sticking it into his pocket.

"Are you still so sure we're ningen?" Hiei questioned.

Yusuke smirked slightly. "Yeah, third eye is a pretty effective away to prove you're not, I guess."

Kurama sighed, moving small vines to encircle Robin's feet, just in case the fighting started up again. "If it isn't obvious enough already, the three of us are Youkai from the Makai; we live in Japan currently; well, somewhat. If that is all, we have done what we came here for, and it is about time that we returned to Reikai to receive our mission.

Neither the police nor the Batman replied, and so Kurama and Yusuke began walking away. Hiei stood still, glaring at the ningen who were still staring at him and his third eye. Eventually, as it became clear they weren't paying any attention to his glare, he moved so quickly as to disappear entirely from their sight.

Yin blinked. "I'm going to take Poison Ivy into custody…" she muttered softly, returning to work and trying to take her mind off of this strange occurrence.

Batman nodded, pushing his apprentices forward. He hadn't thought he had pushed Robin very hard, but the boy still tripped. Batman ignored it, concentrating on getting back to the Batcave, back to work, and back on the lookout for those strangers.

A/N- I might make it a three-shot if I have any inspiration to make Yusuke fight a Batman villain, but other than that, this is complete. This one was nine pages long.

If you enjoyed this story, I'd appreciate it if you left a review, or chose to look at one of my other stories. Thanks for reading.

Sayonara!

Shiori Hitohana