In spirit world, Koenma was stamping away at papers at his desk when Jorge burst through his office doors. "Koenma sir!" he shouted, "We have a report on Hiei." He held a paper above his head and ran over to him.

"Well, spit it out," he said, "nevermind just hand it to me." He took the paper. "This is troubling."

"What does it say sir?" Jorge asked nervously.

Koenma asked, "You mean to tell me you didn't read it yet?"

"Well uh," he replied sheepishly, "no sir. I couldn't understand what it was saying. What does it say?"

"You idiot," Koenma said, "it says here it's a residual effect of the poison. His body is rejecting both spirit and demon energy."

"What?" Jorge asked, "Is that even possible? How is he supposed to recover from his injuries or ever get his demon energy back? Does that mean he's stuck like this forever?"

"That Chikara," Koenma said, ignoring Jorge completely like usual, "what an evil demon. I'm glad Kurama killed him. I'll tell Genkai right away what we know so far."

"What the hell is that supposed to mean?" Hiei demanded. His shirt and jacket were newly cleaned but his injuries from Kurama's rose whip were still having trouble healing, even after a full week. It never took him this long to heal before.

Yukina said, "This doesn't sound good."

Genkai replied, "It means for the time being you're stuck like this, at least with the information that we know." She cleared away more debris and started cleaning up her temple some more.

Hiei growled at her. Yukina said, "This isn't her fault!"

"How is this possible?" he asked, "How can poison do that?"

"I've never seen something like this happen," Genkai admitted, "then again, I've only ever heard of black blood poisoning and never seen it's effects in person."

"Don't tell me I have to live here forever," he said angrily walking away. Once he was outside he tried his flame again but nothing happened.

Back in spirit world Koenma rounded up everyone (Botan, Kurama, and Yusuke). He explained, "I finally found it, a bone marrow transplant should do the trick."

Yusuke said, "Alright, what the hell is that?"

Kurama explained, "In the middle of your bones, or bone marrow, your body creates blood cells. If Hiei gets a new one from someone else he should be able to fully recover."

"How do we know that this is supposed to work?" Botan asked, "You said before that Yukina's energy should do the trick."

"That was before I finished reading this book," he confessed, "which we also have a problem. Demon bone marrows and human bone marrows don't mix so Kurama, Yusuke, get tested."

Yusuke replied, "But what if we don't match?"

Koenma said, "We'll have to convince Yukina to get tested, she'll most likely be a match since she's actually related to Hiei."

"I'm so sick of lying to her," Botan said.

"So you want to get killed by Hiei?" Yusuke asked, "He still has a sword and a bad temper."

Kurama said, "I'll mention that it's best she try and get tested too, just because she's a demon."

Several days later at Genkai's temple (which was being rebuilt and under construction) Botan, Yukina, Genkai, Kurama, Yusuke, Kuwabara, and Hiei are all together again. Hiei was sitting off to the side as usual.

"Well this is interesting," Botan said, looking at the results.

"Just tell us already!" Yusuke demanded.

"Yusuke's not a match at all," she explained, "but if we had to use Kurama we could, it's close enough that it shouldn't be an issue. Yukina's a perfect match."

Yukina asked, "Really?" She looked over at Hiei who was sitting at the door and looking outside, ignoring all of them.

Kuwabara asked, "How is that possible? They're not even the same race of demon!"

"It's more complicated than that," Kurama replied.

"I thought you could only be a match if you were related," Kuwabara said.

Kurama explained, trying not to let the secret out, "Kuwabara it's a larger scale than that. Hiei and I aren't related at all but apparently our bone marrows are similar." He looked at the results more closely.