Author's note: There is more Sherlock and Castiel bonding because the scene just grew. I couldn't help it. I am obsessed with parallels, and these two – I can't help but feel they would understand each other.

This chapter is going to be shorter again. Sorry.

I don't own anything, please review.

Cas didn't know anything about physics or chemistry, which surprised Sherlock. If he had indeed been an angel, he must have lived for thousands of years – at least according to the Bible which the consulting had read when he was a teenager – and yet he apparently had never learned anything about reactions or experiments. Even the microscope seemed to fascinate him.

It wasn't that Sherlock had never had anyone to listen to him when he explained one of his experiments; John occasionally wanted to know what he was doing, and Molly was always glad to help. But he had never seen someone who was so focused on what he had to tell them. Castiel looked him into the eyes while he talked, asked questions when he didn't understand something immediately, was genuinely interested.

He gave Sherlock the feeling that he was genuinely interested in what he was explaining. Molly knew most of what he told her because she was a pathologist, and a good one at that; John was curious because he was his friend.

Cas, however, was interested in everything. In him, in the sample, in the microscope.

It was difficult to explain, even for Sherlock.

Maybe this was one of the reasons he believed what Castiel had told him: the other man simply didn't seem like he'd lived his life on this Earth.

"And what exactly do you hope to achieve with the results of this experiment?" Cas asked as Sherlock added another chemical to another sample.

"It will help me identify the different types of acids used on dead tissue in hopes of destroying the evidence".

"And therefore you will ensure that murderers are convicted?"

"Not only murderers."

Cas nodded and stared at the microscope again.

"It is fascinating. I never met a scientist before".

"I am a consulting detective."

"As my friend Dean would say, "Close enough"" Cas answered, smiling.

Sherlock stared at the sample, not sure how to phrase his next question. Even though he was sure, for reasons he couldn't name, that the former angel wouldn't be angry, no matter what he said. Somehow they understood each other; maybe because they had both lived most of their lives without any human connection. It didn't matter.

"You are a hunter now" he stated carefully and Cas replied "Of course".

"And you haven't thought of doing something else? You could study chemistry. If it interests you that much".

Cas looked down at his folded hands in his lap. "I am aware of that" he said. "In fact, before I was courageous enough to find Dean – and Sam – I thought about it. About starting a new life. But they are my friends. I belong at their side".

Sherlock nodded, but Castiel didn't see it and continued, "Like you and John. We are parts of a whole".

"How did you meet?" Sherlock was genuinely interested, which didn't happen often, at least not with other living people. But Cas had been an angel, and he couldn't deduce him.

"I grabbed Dean tight and raised him from perdition. I met his brother soon afterwards".

"Are you saying – "

"Dean was in Hell" Cas said simply, "and it was my job, as you would say, to pull him out". He didn't elaborate, but it wasn't necessary.

Sherlock saw that he was telling the truth.

He had been convinced that Dean knew more about Hell than he let on based on his facial expression when he'd told him how long Moriarty had been there.

As selfish as it was, he couldn't help but feel that Cas might be right about him after all, if he had been to Hell.

"John had been invalided home from Afghanistan" he finally said "and he was – he wasn't doing well. A mutual friend introduced us."

Before John, he would never have considered Mike Stamford a friend – he wouldn't have considered anyone a friend. The doctor had changed him, just like saving Dean seemed to have changed Castiel.

"And since then you have been there for each other". Castiel's eyes sparkled, although something like regret dulled them, and Sherlock shook his head.

"When Moriarty was still alive – we played games. Eventually, I had to convince everyone, even my friends, even John, that I was dead. I was gone for three years".

"I know. I read the file. But you did it for their safety?" Cas' eyes bored into his.

"Yes."

"I left Dean and his brother alone for months at a time. And I certainly didn't do it so they could be safe".

They stared at each other for a moment before starting to laugh.

Perhaps that was why they understood one another. They both weren't exactly the best friends one could hope for.

Sherlock grew serious again. There was one question that had been on his mind since they left Mycroft's house, one question he didn't think Sam or Dean would answer honestly.

Cas, on the other hand –

"What if we can't trap Moriarty? What if we can't exorcise him? Is there another way to stop him?"

"Yes" Cas said slowly, completely unfazed by the change of topic, most likely because he was accustomed of doing the same himself. "We can burn his bones. It will kill him. I realized there was no mention of Moriarty's grave in the file".

"Mycroft had his body removed to "save my reputation" since he believed the discovery of Rich Brook's body" – Sherlock waited for Castiel to indicate that he remembered who Rich Brook was before continuing – "would only prove that I had been a fraud. He had him buried on a small field about two hours from here".

The former angel but didn't answer and Sherlock demanded, "What will happen to Mycroft if we burn the bones? There has to be a reason you didn't mention it before".

"When the bones of a demon are burned his vessel is destroyed" Cas answered. "If we have to resort to this, Mycroft will die".

His bluntness would have shocked anyone else, but it was fine by Sherlock. He had asked for the truth and he had got it.

"You are saying that all things considered there is a great chance my brother will die regardless" he stated and Cas nodded.

"I am sorry."

"Don't be. As long as he isn't possessed by Moriarty anymore – death is preferable."

Cas didn't flinch, didn't seem shocked, and for that Sherlock was grateful. Normal people tended to believe he didn't care whenever he told the truth.

But he did care. He had known Mycroft all his life, and despite his "betrayal" he still trusted him. And now he needed his help.

He didn't want to let his brother down. He didn't want to kill him.

"What does this do?" Cas inquired suddenly, pointing at another bottle, obviously trying to make Sherlock feel better in the most obvious way possible.

The consulting detective didn't comment on it.

If he had attempted to console someone, it would perhaps have been equally obvious.

He was still showing Castiel what he could do with the various chemicals and pieces of equipment he had when John stumbled into the kitchen. Sherlock was at his side in an instant, noted that the sun had risen, and quickly checked the time.

It was almost 8 am.

"How are you feeling?"

John blinked. "Better. The Winchesters are still asleep, I wanted to check on you".

"It's alright, John" Cas said. "I kept Sherlock company".

John blinked again, looked at Sherlock who nodded and then went to make tea, shaking his head.

"I saw you gave them Moriarty's file" he commented while putting the kettle on.

"I did. They have to know what we are up against."

"He has all the power of the British Government. Do you think he'll try to have us arrested?"

"No" Cas replied instead of Sherlock, surprising them both; solving cases, talking about criminals was so much part of their usual routine that they had almost forgotten the former angel was still in their kitchen.

Sherlock remembered he had to tell John at some point what Cas had told him in the night. He doubted it would be an easy conversation.

While they were drinking their tea – Castiel had happily accepted a cup since "he'd never tried it before", which seemed to confuse John for a moment before he remembered he was American – Sam and Dean woke up and wandered into the kitchen, rubbing their eyes.

The elder Winchester sighed when he realized they had only made tea and not coffee, but drank it nonetheless; Sam accepted his cup with a simple "Thank you".

"What do we do now?" John asked once they had all migrated into the living room since their kitchen was too small. He still looked pale, but Sherlock knew he would decline any offer of more rest.

"We could always find a secluded spot and summon him."

"Unless we could summon him directly into the Devil's trap, it wouldn't work, not according to his file" Sam reminded him, "and he doesn't have to come".

Dean sighed and looked at the table.

Sherlock's phone rang.

It was Greg. He picked up, listened for a minute, told the DI stiffly that they would be there and hung up.

He looked at the faces of his companions before explaining, "The Minister of Foreign Affairs has been murdered. The Game is on".

Author's note: Like I said, the whole Sherlock and Castiel conversation got slightly out of hand. I regret nothing.

I hope you liked it, please review.