Kurama was tending to the last of his plants when Hiei showed up at his window, and right away he could tell something wasn't right.

"Hiei, come in and sit down," Kurama said, and when Hiei had done so, Kurama closed the window and turned to the fire demon.

"What happened?"

"More like 'what's happening'," he growled, stiff and tense, "I would also like to know, as I have no clue."

"Try to explain," Kurama coaxed, taking a seat on his bed, his small watering can dangling from his fingers which were resting by his thighs.

"I have the most… overwhelming… urge to have sex."

Kurama blinked. Well, that wasn't what he expected.

"How long has this been going on?" He asked, and Hiei gave a small shrug.

"Just today."

"How have you been dealing with it?" Kurama asked, concerned.

"Ignoring it."

Kurama hummed in acknowledgement. He had never heard of this happening to male demons. Female ones, yes, but not males.

'Though he is the only male of a completely female demon race. Maybe…'

"I have a theory of what this could be happening."

"I was looking for a way to fix this," Hiei snapped, and Kurama nodded.

"I may have that too," Kurama took a breath. "You have Koorime blood in your veins, and even though you are male, Koorime instincts are putting you in a kind of… 'heat'. Since you can't give birth, your instincts are trying to get you to reproduce instead."

Hiei was silent, but nodded. Kurama took this a sign to continue.

"So the only way to cure this, is for you to follow your instincts and have sex with someone."

Hiei looked at him startled for a moment, then shook his head. "I don't see that happening."

"It may be the only way."

"I won't just have sex with anyone, definitely just because I feel compelled to either!"

"What if…" Kurama hesitated, which grabbed Hiei's full attention. Kurama never hesitated.

"What if I let you have sex with me?"

Hiei was stunned. This wasn't a light offer. But Hiei thought about it too. Kurama wasn't just anybody; he trusted Kurama to a large extent. Could he trust Kurama with fixing this?

"I don't want to use you like that, like you're a whore."

"I didn't think you would 'use' me like that, and I am offering as a friend and comrade. You need this, let me help."

Hiei was silent once more, but nodded his consent to the idea. He didn't move though, so Kurama took the initiative and slid off the bed and in front of Hiei, so that they were eye level, and captured his lips in a gentle, reassuring kiss. Kurama didn't move to deepen the kiss, but slowly let Hiei take control and lead this, like his instincts wanted him to. When Hiei did finally start taking dominance, Kurama willed himself to be submissive, though his instincts were telling him to take control.

Kurama's last coherent thought was, 'I hope this works…'

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Kurama woke up later that night (though it was rather early morning) to see Hiei sitting in the desk chair again.

"Hey," Kurama greeted softly, "feel better?"

Hiei nodded, looking slightly ashamed. Kurama didn't take that personally. He had a feeling he knew what Hiei was ashamed of.

"Don't think too much about it. We all lose control at time."

"I shouldn't have used you like that."

"You didn't use me, I offered myself to you. And I would do it again if needed."

"You shouldn't have had to do that!"

Kurama narrowed a level look at Hiei.

"Instinct is hard to fight. A lesser demon would have raped someone. Be glad it didn't fall to that. You controlled yourself magnificently, don't think so little of yourself."

Hiei didn't say anything after that, though he did look slightly mollified.

Kurama grabbed a change of clothes, and headed towards the bathroom. Before he left his bedroom though, he said to Hiei, "I'm going to Genkai's temple today to talk to Yukina about Koorime instincts and traditions when it comes to mating. That may shed some light on your condition." Hiei looked ready to yell at him, so Kurama added, "I won't mention you. I'll just merely be curious about her and Kuwabara's engagement." This didn't seem to calm Hiei down any, but Kurama left before he could shout at him.

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Kurama took a long shower, and spent even more time drying his hair and dressing. He thought about last night, and found that he didn't regret what had happened. It didn't mean anything, really, besides a release for Hiei's instinctive reproducing. He was glad though, that it had worked, and that Hiei's body couldn't tell that he wasn't the right gender.

He didn't feel awkward around Hiei either, unlike most human men who just had sex with their best friend. It wasn't like they were suddenly lovers, or had to live up to new expectations because they had sex. They simply had sex, back to normal. And if it happened again to Hiei, Kurama would make the same offer.

Kurama finally stepped out of the bathroom forty-five minutes later, ready to take the long journey to Genkai's temple. Hiei had left by the time Kurama re-entered his bedroom to grab a jacket – it was the middle of winter – and Kurama didn't think too much of it.

By the time he reached the temple, day had finally begun, and Yukina greeted him at the top of the stairs.

"Hello Kurama-san, what brings you today?"

"I actually had some questions for you, about some Koorime customs," Kurama said, and Yukina smiled.

"Let me make some tea, and we'll talk."

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Kurama sipped at his tea, and Yukina just smiled pleasantly at him.

"So what would you like to know?"

"I know you and Kuwabara are engaged, so I thought I'd ask some questions, so if he asks, I can be prepared." Yukina didn't take offense to this – Kurama was approached the most often with questions from Yuusuke and Kuwabara on demon related topics. Hiei didn't have the patience, and Yukina was too isolated from the rest of the Demon Realm to know much else than her island.

Kurama took a breath, and asked, "When do the Koorime usually go into heat?"

"Heat? I do not understand," Yukina responded with her own question. So Kurama explained.

"When your body tells you it's time to reproduce."

"Oh! I think I understand. We don't go into 'heat' like most demon females. We reproduce asexually, so when we turn 100 human years old, we have our first chance of bearing a child."

"What does that entail, exactly?"

"Well, like most females, we have a reproductive system, but instead of needing a male to have children – though we still can – when we turn 100, a single egg releases into our womb. We then push energy into that egg, and it fertilizes. Since there isn't a male chromosome present, all children are guaranteed to be female. The risks of males only come when we reproduce with a male."

Kurama was doing quick calculations in his head. When they turn 100…

"When did you reach age?"

"Just yesterday, actually."

Oh God. He had sex with the demon equivalent of a child?!

"This has to do with Hiei-san, doesn't it."

Kurama was pulled out of his thoughts abruptly. 'What?'

"Hiei?"

"I know he's my brother; his energy is very similar to mine. Why he won't tell me, I can only speculate it has to do with what he did in the Demon Realm growing up. Until he feels ready to tell me, I'll just seem oblivious. But he turned 100 yesterday also… something happened, didn't it?"

Kurama could only nod.

"He had the strongest instincts to have sex. I'm guessing because he is male, but still Koorime."

"Yes, most likely," Yukina agreed, and then looked at Kurama.

"You had sex with him, to try to help."

"Yes, I did."

"And now you're regretting it."

"I never knew his age. I didn't know he was still a child!" Kurama was given a knowing look from Yukina.

"Female fox demons usually don't go into their first heat until they reach their 250th spring. So to you, Hiei-san is still a child. However, Koorime reach full adult maturity at 100. So he isn't really a child. To him, you are the child."

"But I'm much older than he is."

"Not physically. You are only 20 in this body. Barely anything in demon years."

Kurama could only nod. She did have a point.

"Will this happen to Hiei again?" Kurama asked, steering the subject back to the real point of why he was here.

"Every year on this date. I am glad you managed to find a cure for his instincts right now; I don't know much else that can help him. Male demons that have instincts like a female's are pretty few and far between."

"I know."

"Help him, or find someone who can. It must have been unbearable for him to actually seek help."

Kurama finished his tea, and stood up.

"Thank you, Yukina, for the insight."

"You're very welcome Kurama-san."

As they walked outside, Kurama turned to Yukina.

"Did you…"

"I almost did. But I would rather have children with Kazuma then have one instinctively on my own."

"You really love him, don't you?"

"Love is something I know little about when it comes to a life partner. But I am rather fond of Kazuma, and he understands. He just says he'll teach me how to love. I look forward to this human concept."

Kurama headed home after that, and the journey back to his small home, thought about what he learned.

Every year Hiei would need sex, if it was the same as this year. Kurama was ready for that. Until Hiei found a partner or someone he wanted to have children with, Kurama would offer himself for Hiei to quell his desires. It was safe, risk free, and had no strings attached for either of them. They were both demons, not humans who saw meaning with every little act.

A wicked thought entered Kurama's mind.

'I am so throwing him a human birthday party with everyone.'

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