So, this is my attempt to capture the likely very complicated thoughts and feelings Natori experienced when Takashi told him about the Book of Friends. I'm not sure I did it justice, but I tried as best I could. It's a bit weird referring to Natori by his given name, but I can't imagine he refers to himself in his head as 'Natori,', so 'Shuuichi' it is when I write his POV.

I own nothing.

The drive back down from the mountains was a quiet one. Most everyone else had already left Hakozaki's place, so at least the roads weren't crowded; only Hakozaki's granddaughter remained, sitting beneath the maple tree with an inscrutable look on her face. What spells they'd salvaged from the fire were tucked safely away in the glove compartment, out of sight of prying eyes until Shuuichi could get them back into his apartment and transcribed. Hiiragi and Urihime and Sasago had gone on ahead; they could travel faster than Shuuichi could drive his car, and none of them really liked riding in the car anyways (Not since Urihime had last gotten motion sickness riding in the back, at least). It was late in the day, and it had been agreed that Shuuichi would just drive Takashi back to his house instead of to the train station. Takashi's cat-dog-thing kept fussing about getting food, but Takashi paid him little mind, instead staring out the window, smiling absently at the yellowing leaves on the trees around them.

Himself, Shuuichi was so preoccupied by what he'd learned that he could barely pay attention to the road, let alone try to make conversation with his passengers.

He had spent more than a month trying to figure out what the Book of Friends was. Neither Sasago nor Urihime had had any idea of what it was—nor, it happened, had Hiiragi, though she had said so little on the subject that Shuuichi was beginning to wonder if that had really been the case after all. Considering what he had learned, Shuuichi supposed he could understand her caution; a hint sure would have been nice, though.

A month spent leafing through every journal and research book he owned, looking for even the slightest clue towards what the Book of Friends was. Shuuichi found nothing among his own materials. Failing that, he'd gone to Takuma's house for help.

"Take the lot," Takuma had muttered, pressing a key into his hand and pointing to a locked chest, while Tsukiko asked, too-brightly, what had been happening with his acting lately and Ginro eyed the proceedings sharply, a shadow in the room that only Shuuichi could see. "It's not like I have any use for it anymore, and it's too dangerous to destroy." (Shuuichi gawked at him for a moment, rather stunned at such a display of trust, but he took the key and the chest, nonetheless.)

And, granted, Shuuichi had found a lot of information in Takuma's notes that would be useful in the future, but nothing about the Book of Friends. He tried to ask Ginro—surely Ginro would know, considering she was the one who'd first mentioned it—but Ginro had only glared at him and vanished. No amount of scouring the house could tell him where she had hidden, and bereft of the desire to needlessly worry his old mentor or Tsukiko, Shuuichi left without trying to draw Ginro out.

A month spent trekking the backwoods and the remote hills on exorcism jobs, asking what ayakashi he could find if they had any idea what the Book of Friends was. Some seemed to know, and others didn't, but anyone who didn't end up sealed or exorcised wound up running away before Shuuichi could ask anything more than 'What is it?' The way they responded, coupled with how Ginro had talked when she first cornered Takashi, only made Shuuichi even more certain that whatever it was Takashi had, it was something dangerous, something considered dangerous in the hands of an exorcist. It wasn't something Takashi should be holding onto by himself.

Shuuichi had even gone so far as to visit the old family house, for all the good that had done him. He, ah, hadn't exactly parted from his father and grandfather on good terms, and the fact that his grandfather had died in the nearly five years it had been since he had left home did nothing to change that. He supposed he should just be glad his father hadn't slammed the front door in his face. I shouldn't have expected him to be forthcoming, though that's my fault, I guess. Heh… His uncles had been a touch friendlier, but not by much, and they hadn't been any more cooperative than his father.

A month spent pondering.

Eventually, his shiki had grown exasperated with him, declared themselves done, and Sasago had thrown her hands up in the air and told him to just ask Takashi what the Book of Friends was. "He's your friend, isn't he? If you ask him, he should tell you."

"Maybe, but sometimes I wonder…"

Takashi was always getting into some kind of trouble with the ayakashi that hung around the town where he lived. He wasn't the kind of kid who went around picking fights. Shuuichi knew Takashi was just trying to live a normal life with his foster parents, but trouble still seemed to find him, no matter where he went. There was something else, then, and it made Shuuichi nervous to think about. Yes, he'd admit that he was nervous. There was something that was putting him at risk, and Shuuichi had no idea what.

He thought back to his own high-school days, when he was Takashi's age. If he had been holding on to something dangerous in those days, something dangerous for an exorcist to possess either because of risk posed to himself or to ayakashi, would he had told, say, Takuma, that he had it? Likely not. More likely, Shuuichi admitted ruefully, I would have held onto it and used it to increase my own prestige or as insurance against ayakashi who would have otherwise tried to hurt me. Even if I was risking getting sanctioned, or even blacklisted. I think Natsume's a bit smarter than I was at that age. Or if he's just as foolhardy, it's not in the same way.

He didn't think Takashi would tell him. He didn't think it was a good idea to try to force the issue. He'd figure out what the Book of Friends was on his own, and move from there—whether to leave it in Takashi hands or try to take it from him, Shuuichi didn't know. (He liked to believe that he could move himself to act, if the latter action was necessary. He liked to believe he could do it without feeling guilty. Funny how his own feelings kept making a liar of him.)

But the funny thing is, Takashi did tell him. And what he'd told him was, in a way, far worse than anything Shuuichi could have imagined on his own.

One of the first things Takuma had taught him, when he was finally persuaded to teach Shuuichi anything, was that when making contracts of any kind with ayakashi, to never use his real name, and to never have the ayakashi use their real names either. Names had power, and the potential for misuse and abuse of that power was enormous. It was cruel, it was dangerous, and it was expressly forbidden among exorcists for those reasons.

Natsume Reiko, were she an exorcist, would have been blacklisted from the community for creating something like the Book of Friends. Natsume Takashi, were he an exorcist, would have been severely sanctioned for carrying it, even if his intent was to free the ayakashi whose names were catalogued inside. At least now I know why he went so pale when I was telling him about forbidden contracts. …Good God, how long has he been dealing with this by himself?

But Reiko was not an exorcist. The name 'Natsume' had never come up in any documents relating to exorcists that Shuuichi had read; he had never heard the name mentioned at any meetings he attended, at least not before meeting Takashi. The closest Reiko came to being associated with exorcists (as far as Shuuichi knew) was that Nanase had apparently heard of her: heard of her, not known her. Reiko was not an exorcist; any deed or misdeed of hers fell outside the community's purview. The power of names was knowledge she could easily have come upon elsewhere; any library book about the supernatural could have told her as much.

…Reiko, from what Takashi had told him, was not a happy person. She sounded… Well, it was difficult for Shuuichi to say what she sounded like; the way Takashi described her, she seemed almost inhuman, more like a force of nature than either a human or an ayakashi. What Shuuichi knew for certain was that she sounded lonely and above all angry. He couldn't even guess why she made ayakashi write their names down in her book, since Takashi said that she typically completely snubbed anyone whose names were in the book. Takashi thought that she took her anger at humans out on ayakashi, but in the same breath he wondered if maybe she was just looking for someone who would care about her, in amongst the multitude that had turned their backs.

"I don't know," Takashi murmured, resting his chin upon his knees, brow deeply furrowed. "I don't know a whole lot about her apart from… this. But I think she must have wanted someone who…" He frowned unhappily and broke off, shoulders stiffening.

"Natsume…" Shuuichi reached out and put a hand on Takashi's shoulder, but before he could say anything more, Nyanko-sensei interrupted him.

"Tangled hair, skinned knees and chapped hands." The round cat was rolling about in the grass, eyeing them both with a narrowed gaze. "A frozen smile and laughing eyes, though the laughter was rarely genuine. Or kind. That was Reiko. Still, you'd catch her doing small things. Kind things. No one ever knew why. Half the time, neither did she." Nyanko-sensei snorted. "You humans. Even when you make a go at killing your heart, you can never do it cleanly. Don't you agree?"

The question sounded pretty pointed, and Shuuichi squared his shoulders defensively. Takashi shot a warning glance at his self-proclaimed (if rather abysmal at the job) bodyguard, but Shuuichi shook his head and smiled sharply at the cat. "You sound like you knew her pretty well."

"Oh, I did. We came to know each other quite well over the years. She tried to get my name more than once, but I knew better. I don't come when called."

It seemed that the reason for Takashi's never-ending troubles with ayakashi could be laid at his grandmother's doorstep. A woman like that doubtless had many enemies, and indeed, Takashi had apparently been attacked several times by ayakashi over Reiko's book. There were those who wanted their names back; there were those who wanted the book for themselves. The common thread was that the ayakashi didn't just attack Takashi because he was Reiko's grandson; they attacked him because they thought he was Reiko.

So, will he be stuck cleaning up this mess for the rest of his life, then? Will they finally leave him alone when he's cleared out the book, or will they keep coming after him, even then?

That book… Shuuichi was more convinced than ever that it wasn't something safe for Takashi to have. It was like a flame that drew not just moths, but wasps as well. But he wouldn't be out of danger even if the Book of Friends was done away with—and destroying the book would just kill the ayakashi whose names are still inside; Natsume would never agree to that. Even if Takashi no longer had the Book of Friends, there would be those who thought he had it, and for ayakashi, family resemblances went deeper than the outward appearance; Takashi's blood would still have the same smell as Reiko's even if he were to change his appearance. Shuuichi wondered if Takashi lived with that knowledge the way he lived with the lizard that crawled under his skin, or the way Seiji lived with the charm over his eye, a threat that was just waiting to fulfill itself, waiting for you to let your guard down. The seed of uncertainty that left you glancing back over your shoulder, every day, left you waiting for an attack, and more surprised when it didn't come.

Just giving the names back with no thought to his own gain or safety; that's just like him. Shuuichi managed a fond smile at Takashi, though, still staring out the window, he didn't see it. I wonder if Natsume has a single self-serving bone in his body.

But I bet his altruism gets him into even more trouble, sometimes. I wish I…

Shuuichi shook that thought away. It wouldn't do him any good, not here, not now.

The yellow leaves were starting to turn red from the sunset when Shuuichi finally pulled up in front of the Fujiwaras' house. "Thanks for driving me back, Natori-san," Takashi murmured as he unclipped his seat belt and opened the door so Nyanko-sensei could hop out.

"It's not a problem. I'll see you around." Then, Shuuichi frowned, and caught Takashi's shoulder before he could get out of the car. Takashi's eyebrows shot up, but he didn't protest—well, he wasn't protesting yet, anyways. Nyanko-sensei sat by the gate, and though his expression was always frozen in that enigmatic look, Shuuichi thought the ayakashi was looking at him rather warily. "Listen, Natsume…" He paused, searching Takashi's face while he tried to put the words together. Why is this so hard to say, always so hard to say? "You… You're a good kid. I've seen people take advantage of you over that—" Hell, I've taken advantage of you over that "—and sometimes I wonder if you aren't getting in over your head with things. I… I don't want you to get hurt. If you get in trouble, with ayakashi, humans, anyone, I want you to call me." Never mind that he'd already told Takashi this once before. "Alright?"

Takashi stared silently at him for a long moment, eyes wide. In the silence, his words still ringing in his ears, Shuuichi began to wonder if he hadn't said just a bit too much. Come on, this isn't like the movies; that might have been a bit too melodramatic for the real world. I wonder how long it'll take before he starts laughing at me.

But instead of laughing, Takashi just smiled. "I will. But you know you can call me too, right?"

"I do, Natsume. And I will. Good night."

After Takashi and Nyanko-sensei slipped through the gate and out of sight, Shuuichi sat in the car, frowning deeply.

It might have been his imagination, but he thought that something had changed about the way Takashi smiled since they had first met. His smiles felt much warmer, somehow. Shuuichi… He was glad of that. He didn't want to be the one responsible for those smiles growing cool again.

Regarding the Book of Friends, his first instinct was to just march into the Fujiwaras' house, find the thing and toss it on the nearest bonfire. Shuuichi might have done just that if he had learned of the Book of Friends when he first met Takashi, regardless of the boy's protests, uncaring if this would have poisoned what relationship they had forever. He shuddered to think of what the book might be used for if it fell into the wrong hands, and at the beginning, even if Takashi had hated him for it, Shuuichi still would have destroyed it.

He also wouldn't lie and say he hadn't had a moment when he thought about taking it for himself. To protect Takashi, or at least that was what Shuuichi had thought to justify the desire to himself. In reality, he knew it wasn't something so altruistic as that. An exorcist needed clout; they needed something, anything that would give them an advantage over the others, or they were risking getting thrown under the bus. Oftentimes that clout carried its own risk, was something that could get you in a lot of trouble if you were caught, but Shuuichi could still remember something he'd been told, a long time ago—"You only get in trouble if you get caught." It wasn't about wanting. It was about needing.

But then, I'm not the person I once was either. Natsume's not the only one who's changed.

Any exorcist worth their salt had secrets. They had things they didn't share with anyone, not their colleagues, not their friends, not their shiki, not their apprentices, not even their closest family. Confiding in others was a good way to get torn apart, either figuratively or literally (There was still a stain on the floor of the hall at Ishizuki). Would Shuuichi have trusted one of his colleagues with a secret like this? Would they have trusted him?

No. Only Takashi would.

So, regardless of his own misgivings, Shuuichi would repay that trust as best he could. It was the least he could do.

I still think there's the potential for future Book of Friends-related drama between Takashi and Natori, but I also think the worst of it was averted when Takashi chose to tell him, instead of leaving him to figure it all out on his own.