A traumatic or even simply surprising experience can cause one's soul to separate from the body.
Kazuma considers the possibility of suffering from such an affliction.
Kazuma sighs, and slouches further in his chair to the point that he's not even sitting anymore.
"Are you okay?" Naruhodou asks him worriedly. Kazuma would wave it off, but he knows that dismissing Naruhodou's concern will only make it worse.
"More of the usual," Kazuma explains, and puts his arm over his eyes.
He's felt this exhaustion ever since he regained his memories in London. It's not quite that his energy is being drained, but rather that it never seems to be there at all. He wakes up tired, goes through his day tired, eats his meals tired, goes to bed tired. He doesn't tire easily; he's just tired to begin with. No amount of sleeping, feeding himself, exercising, or allowing himself private time to recover his social energy has helped him. He's just... so, so drained.
Kazuma can tell that Naruhodou is watching him. He feels the gaze on him, flickering from his head to his chest to his legs to his head again. The sensation of being watched isn't exactly unusual, but Kazuma had come to learn that it wasn't normal to be able to pinpoint with that kind of accuracy exactly where he was being watched. It's another one of the little oddities that he inherited from his mother, inclined toward the spiritual as she had been.
She had gone through great exhaustion too, before she died. The thought of it twists Kazuma's chest. He doesn't want to think about it, and curses his mind for making the logical leap there. She had died of sickness, bedbound and unable to care for herself. Kazuma is still well enough to work at the law office, run errands, cook with Naruhodou, clean up around the house, so on and so forth. He's not anywhere near as sick as his mother had been. He's fine.
"You're not fine," Naruhodou says, and Kazuma removes his arm to see two deeply annoyed brown eyes staring into his own.
"I'm just tired," he tells Naruhodou. This does not deter Naruhodou, who is clearly set on finding out what is going on.
"You're always tired. I know you're sleeping and eating, but you never have any energy. I'm worried, Asougi."
Oh god, there it is. Naruhodou is worried. The worst thing to do to Naruhodou, really, because once Naruhodou starts worrying he never stops worrying until the problem is completely solved. He's just very empathetic like that. The problem is that most of Kazuma's problems can't be easily solved and squared away like paperwork piled up on a desk. They start from places that Naruhodou just can't reach, and end in things that Kazuma can barely understand himself. Try telling that to Naruhodou, though. He would just try harder to do the impossible.
"Don't apologize. You're not doing anything wrong. It's just... you know. I'm worried. I don't want you to get sick."
Like your mother goes unsaid. Maybe Kazuma is just projecting that Naruhodou would think that way.
"I don't know what else to do," Kazuma replies, rubbing his face. He's asked Dr. Mikotoba for help, gone to a few doctors who gave him advice and some medicines, but none have helped deal with this exhaustion. "I feel like it's permeating all the way into my heart and soul."
There's a brief bit of silence in words, although Kazuma continues to sigh and exhale as he tries to expirate all of the weariness in him.
"Do you think... you might have lost your mabui?"
Kazuma sits up the barest amount straighter and stares at Naruhodou. He does, to his credit, not give any indication of feeling any bit of hesitance for what he just said.
"You've been exhausted all this time even though you're taking care of yourself. I mean, I know you're.. well, injured, basically, so you're having trouble with things like memory or controlling outbursts and the other things you told me. But maybe some of the exhaustion is because your soul got lost somewhere? Maybe even in London."
Mabui, the Uchinaaguchi word for "soul" or "spirit." A shock can cause someone's mabui to separate from their body, which is often left behind at the place where the shock occurred. Getting it back isn't very complicated or difficult, but sometimes the separation requires a priestess's expertise. Symptoms of a lost mabui can include exhaustion, periods of unresponsiveness, and sometimes even catatonia. Kazuma can see where Naruhodou is coming from with this, but...
"That was... a decent amount of time ago," Kazuma points out.
"And you've said that you've been feeling really tired all the time since... you know. The end of that trial," Naruhodou counters, with the swift planning of a true lawyer. "What if your mabui got separated then?"
Kazuma leans back in the chair again at the use of that term. It's incredibly rare that either of them bring up any Uchinaaguchi in conversation for the reason of being unable to actually speak it, but snippets of vocabulary that the government hasn't been able to grind away still make their way into their private discussions.
(Always and only private, because speaking it in public would cause A Lot Of Problems.)
"Okay, so let's say that I did lose my mabui in London. I can't do anything about that. I can't easily go back to the Old Bailey find my soul, can I?"
"You could always do a mabuigumi here."
"That might not even work."
"Asougi, it's your spirit. If you call it back, I'm sure it'll come back."
"Okay, fine. I'll think about it," Kazuma says. "If it'll make you feel better."
"The point is to make you feel better," Naruhodou points out irritably. "It's for you, not me."
"I know. I just don't know if it'll do any good."
"Well- You shouldn't do it if you don't feel good about it. You might call something else in, instead."
"I'm absolutely positive that I can avoid having a ghost hitch a ride on my shoulder, if that's something you're actually worried about. ...wait, I thought you didn't believe in ghosts?"
Naruhodou shrugs and refuses to say anything further on the matter, despite Kazuma's questioning.
Naruhodou had a point. Maybe it's not a bad idea to at least try a mabuigumi, and Kazuma is completely certain that he is spiritually aware enough not to accidentally beckon a ghost or a malevolent spirit toward him in the process. Now that he's thinking about it, though...
...where did he lose his mabui?
He had accepted Naruhodou's suggestion without much thought, because it made perfect sense. That first and final trial against Naruhodou had been a massive shock. Bringing up all of that trauma, then followed by the unthinkable reality of what had happened ten years prior to that... it would be reasonable for someone to lose their mabui as a result of it.
But had that really been where he lost it? Kazuma thinks back further. He had already felt a sort of heaviness in his body before that, while he was the voiceless, faceless, identity-less Masked Disciple. The exhaustion could be easily attributed to his brain injury, though. Even now, it's probably more related to having slammed his head into solid wood. So, he lost it aboard the Alaclaire when Nikomina pushed him. That too makes perfect sense; the surprise from being pushed and the sudden terror of falling, followed by hitting his head would easily shock a soul into falling out.
But... that's not where his exhaustion started, was it? He had felt a persistent tiredness before that too, sitting at the desk in his cabin writing in his journal. His insomnia had exacerbated it, but he's certain that even before that night on the Alaclaire, he had not felt rested in a while. Further back, even more, then...
Kazuma's mind settles on the memory of the day he had been accepted on the exchange trip to London.
Of course. He remember that moment well. It was as if all the warmth had left his body the moment he heard the order. Like a wave of water had crashed through him, leaving him freezing inside. The warmth had not returned after that. The sudden weariness would not leave. He had left the room feeling much heavier than he had entered it, and thinking back... he had never recovered. Kazuma rubs his face, letting out a loud, forceful sigh. Maybe he really had dropped his soul in Seishirou Jigoku's office that day, shocked out of his body and left to linger. What a cruel fate, to be caught in such a place.
That was years ago.
His poor, poor soul.
The best course of action is to go to the place where your soul fell out and beckon it back, but it's not as if he can go back there. Even if he could, he definitely wouldn't be able to speak the necessary words out loud at a volume necessary to bring his mabui back. It's probably a good idea to ask Naruhodou for help with this, then.
Kazuma pauses as he picks up a pencil to make a note for himself. It feels odd, to realize that that moment had been the shock that caused him to lose his mabui. Of all the moments in his life to have terrorized him so horribly... that had been the one that knocked his spirit out.
But this wouldn't be the only time, would it? His mother had taught him the words to bring his mabui back should it ever fall out. Children's mabui were the most susceptible to it, she had told him, because they were young. Kazuma remembers that he had wrinkled his nose at that, and declared himself old enough not to suffer from that. His mother had told him not to be so sure, and that he should speak the words anyway after a nasty surprise or even a sneeze just to be safe. Spoken under his breath, of course, or just in his mind. It would be dangerous to say it out loud.
She had also taught him how to properly beckon back a mabui should one be unable to return to the place where it was lost. I was soon after he learned of his father's death. She had taught him because he was to stand guard over her as she beckoned her mabui back, believing that her sudden loss of energy had been caused by the news of her husband's death.
Kazuma isn't sure if she had been successful or not. It doesn't matter in the end; Kazuma doesn't think that losing her mabui had been the cause of his mother's death.
Ask Naruhodou to watch you he writes onto the paper, before placing the note on his desk.
Kazuma imagines the inside of Jigoku's office.
Kazuma imagines his mabui rushing back to his body.
Kazuma reaches out to grab the first of the seven small rice balls laid out in front of him.
He eats the first, then the second, then each one after that, slowly. When he's finished, he picks up the bowl filled with fish miso soup, drinking it slowly. He keeps his eyes closed, his thoughts still on pulling his mabui back to him and keeping it encased in his body. The warmth that goes through his chest is probably from the miso soup.
When he opens his eyes, Naruhodou is sitting directly in front of him, still holding the blade of tied grass.
"You know you can put that down now," Kazuma says.
"I was just making sure!" Naruhodou replies, and puts the tied grass down next to the plate that held the bite-sized rice balls. "So... how do you feel?"
"I'm not sure. Not too different," Kazuma admits. "But I do feel warmer."
"That means it worked."
"That's how you know your mabui came back. You'll feel a warmth in your chest when it comes back, and that's because it's back inside you where it should be."
Naruhodou puts his hand over Kazuma's sternum. That feels warm too.
"I do feel warmer now. Still kind of tired."
"I think that's from a lack of sleep."
It wouldn't hurt to take a nap, Kazuma thinks. He picks up the plate and bowl while Naruhodou pinches the grass again, and the three of them carry the remaining items from the mabuigumi back to the kitchen. Kazuma leaves it all on the counter to take care of later.
"Naptime," he declares to Naruhodou, and lies down on the fainting couch that Holmes had sent them from London. The bright red and dark cherry are an incredible eyesore among the very Japanese furniture, and Kazuma thinks it's incredibly funny as a result.
"Sleep tight," Naruhodou tells him, and plants a quick kiss on his forehead.
Unsurprisingly, Kazuma's exhaustion problem is not instantly cured.
Still, it's a little easier to relax now. He finds it less of a struggle to fall asleep, and even when his mind turns to the unpleasant moments that he would rather keep buried, the memories wash over him and away; existing for a mere moment in his memory, and easily drawn away from the forefront of his mind. Jigoku's words no longer echo in his head during these moments. They are, and then they simply aren't. He does not stress himself over them. He's safe from them now, forever.
Kazuma turns onto his stomach to get into a better position to sleep, tired and ready to let himself rest.
The entire basis of this fic revolves around the headcanon that Kazuma and Ryuunosuke are Uchinanchu/Okinawan/Ryukyuan. They discuss an Uchinanchu religious/cultural concept regarding people's souls the religious/cultural practice of how to retrieve a displaced soul.
Kaz very clearly has a traumatic brain injury during dgs2 (starting with the fact that he hit his head really hard in 1-2 and expanded on by some of his behavior during 2-4 and 2-5). I didn't want to make his TBI symptoms all go away and explain it as "oh it was just him losing his soul!" because that would be horrendously stupid and ableist. I thought it would be nice to see him taking care of himself on an emotional and spiritual level as part of his healing. losing your mabui is a result of a shocking or traumatic event (ranging from normal surprise to intense trauma), and part of getting it back involves trying to figure out where you lost it. It's a way to start facing your trauma in a controlled way, and if you can't remember or have trouble facing it, you have a way to get your mabui back in a safe environment (like your home).
The specifics of a mabuigumi vary from region to region, so this fic used the parts that are consistent across the various versions I found.