This is already completed on my ao3 account, so you can just search the name there.
Otherwise, here's chapter 4:
Natsume looked out the side window of the cable car as it ascended further into the fog. The sides, front, and back all showed the same image- fog so thick that shapes were indiscernible within it. Nyanko was perched on his shoulder, golden eyes squinting to see if his spirit eyes would prove better. It didn't. Natsume sighed at the situation. He turned his head, eyes scanning the back corner of the cable car where he spotted Natori standing, looking out another window. The man looked lost in thought, perhaps thinking of the information he had gathered before coming to the prefecture, or perhaps it was what he found after. Natsume himself could not help but recall the tale from the villagers below the mountain.
-x-
"The mountain has been covered in mist for decades. Ever since I was a child, I could recall the dense fog hanging over it like a cluster of ghosts, haunting and hiding the secrets hidden within. But the stories don't stop there. They continue even before then. Generation after generation. There is no single story that proves true. They all weave together to tell the greater story. The curse of High Field Mountain."
-x-
The cable car suddenly jerked signalling the end of their ride to the mountain. An automatic message buzzed through the intercom almost completely unrecognisable in its distortion. A chill ran the length of Natsume's sides as the door clicked and slid open. Natori climbed the short staircase at the bottom of the car to the door and stepped out into the night. He tried to move forward but the tip of his shoe bumped into something.
"Watch your step, Natsume. There's a staircase right outside, and it seems steep." Natsume followed closely behind him.
Natori seemed to grab hold of something to the side- a railing- and his strides grew more steady. Natsume followed his actions. They made progress up the stairs, but with thick clouds of gray and black beyond that- it seemed never-ending. Natsume's legs grew tired from the ascent when his hand suddenly collided with something; it was thin, almost like strong wire as it shook but did not burst. Natsume drew his hand away quickly, shaking it to make sure nothing remained on his skin. His next step was miscalculated and his body leaned back ready to plunge into oblivion.
-x-
"What kind of curse?" The boy grew in anticipation, wanting to know about the tale that was so rooted in the village's past and still connected to its present.
"One story I remember vividly is one of war. Or maybe...it's easier to accept-the site of a tragic battle that robbed the lives of many- both soldier and common villager alike. War doesn't care what your status is in life."
-x-
Natori quickly grabbed him around the waist- the man's hand gripping the rails in a white-knuckled fist to ensure they both didn't go prematurely plummeting to their deaths.
"Natsume! Are you okay?"
"I'm sorry, I'm fine. Something touched my hand-" The boy cut his words short, not wanting to appear freaked out by the incident. Natori only let him go when they were both firmly standing on their own two feet.
Natori felt something crawling along his hand, using his other to brush it away. He could also feel the threads that seemed to entangle further every time he moved his hand. "It's just a spider. With the fog so thick, I'm sure no one does regular maintenance. Be careful."
Natsume nodded, and resumed his steps. Natori moving behind him for added precaution, but there was no more need for worry as the two both made stumbling steps to even ground at the top.
High above the flat land below, the mountain air was chilly despite the trailing ends of summer. Natsume pulled at his shirt sleeves, tugging them as far as they would go before crossing his arms in front of his chest- the days would probably grow colder as time passed. He allowed himself a small thanks to Touko for making sure he had packed long-sleeved clothes, and one jacket for added measure.
-x-
"Why don't you stay the night? Not only is the fog still so dense, but combined with darkness, it would be too perilous."
"We couldn't possibly impose. And if the night can give us answers as well, it would be best to leave now. But thank you for the offer, and the information."
The exorcist gave his charming smile, but the woman only continued to look saddened as if she were sending someone off to war knowing there would be no chance of their return.
-x-
Natori, Natsume, and Nyanko's heads darted cautiously around, taking in their surroundings. The fog was less dense in the open air but the darkness of night still left their sight hindered.
"I hope it's a lot better in the morning. All this fog isn't going to make things easier." Natori fanned his hand before his eyes before holding it out at length seeing it vanish into nothingness.
"Useless exorcist!" Nyanko chirped close to his ear. Natori's eye twitched as he turned sideways to take in what he could of the fat cat now perched upon his shoulders- Nyanko's eyes glowing a luminescent and eerie golden. "Do you sense anything?"
Natori surveyed the area once more, his eyes furrowed in concentration. "I don't. Nothing too strong at least."
Nyanko nodded slowly at his words, confirming his thoughts- how could a mountain so cursed and steeped in bad energy barely give out a presence?
"Can you do something by transforming?"
"Ha! You doubt me?" Nyanko jumped and spun off of Natori's shoulder blending in with the fog as his cat form disappeared into a puff of smoke. He reappeared not even a second later in his true form- even the large magnificent form barely noticeable in the fog. Madara's large golden eyes narrowed as the swirled, magical sigil upon his forehead glowed a brilliant blue. The fog cleared like a door bursting open. The same door closed just as quickly as the fog once more filled the empty air.
Natsume walked up to their side, his eyes narrowed, unamused. "Natori-san, we should light the lanterns."
"You're right. We shouldn't waste more time out in the open like this." Natori dug around in his pockets to find the matches they were given by the villagers while Natsume retrieved the lamps from the duffle bag slung across his chest.
Nyanko huffed before his giant body disappeared in favour of the chubby lucky-cat mold.
-x-
"There's more isn't there?" The exorcist asked lightly as they were led back to the station in order to make their way up the mountain.
"There are...many other stories. Stories that aren't as believable as fallen soldiers. There's a tale our parents told us to keep us from staying out too late at night. The tale of the crippled wheel.
A woman, hell's servant, attached to a wheel of fire. She rode around the village, and all those who saw her brought sickness and death to their homes. Ones that spoke about seeing her brought the same thing. And after all the sightings, all the gossip- one day, the entire village was gone.
That is the kind of stories you hear about the mountain...if anyone talks about it at all."
-x-
Natsume and Natori each held a lit lantern in front of them, Nyanko once again perched upon the exorcist's shoulder. With the light, they no longer had to strain their eyes in the stark darkness. There were trees on both sides of their walk, each shadow looked more human than the last. Natsume tried to stay as close to the other two as he could but his wandering gaze made him fall behind more often than not.
He had heard Natori's and Nyanko's whispered words earlier, about the lack of presence that the mountain held. It was more than that though- not only did the spirits seem unusually quiet, there were no noises of nature either. Natsume wondered if the mountain creatures had fled because of the fog, or if they lived somewhere else on the mountain.
As he continued to glance at the shadow trees in the distance, an uneasy feeling that they were growing closer swept over him. And that was when he heard it, little chirrups that sounded like thousands and thousands of insects singing in cacophony. As they went on, the sound got louder, grew shriller.
Natsume's lantern slipped from his grip and landed on the floor with a soft thud as his hands flew to his ears in a trivial attempt to block out the noise.
"...me?"
The noises were too loud, they slipped between Natsume's fingers to sing shrilly in his ears.
"...tsume."
The world grew dark as his eyes screwed shut.
"Natsume!"
Something brushed against him, soft like features before he was yanked forward. He opened his eyes and saw that all around him the darkness swirled erratically. A few seconds passed before his eyes and brain caught up and he could tell that the shadows were a swarm of black sparrows flying in tight circles around them. He was standing directly behind Natori now, much closer than they had been when he was trying to drown the song out. Even amidst the birds, he could hear the ghastly cry as they flew closer and closer.
Natori yanked a paper seal from within his pockets, and held it in front of his face. He closed his eyes and weaved words to craft a chant beneath his breath, every word growing louder in volume. When he got to the third repetition, his voice rose to a yell. The birds all opened their beaks one last time- causing Natsume to flinch- as they spread their wings wider and disbursed, melting back into distant shadows.
Natori turned to Natsume, concern would have been fully visible in his eyes if they could see clearly, "Are you all right, Natsume?"
It took a moment before Natsume could speak, the ringing in his ear fading to a phantom memory. He slowly lowered his hands from his ears, and the effect was jarring. All was once again silent- the road was even quieter with the distant memory of sound.
"I'm okay. Didn't that noise bother you, Natori-san?"
At that moment, Nyanko shivered, "There wasn't any sound. Just those creepy birds flying up and down, and opening their beaks in silence." He shivered again for added effect.
Natsume looked at Natori to see if the man agreed. He nodded, and Natsume frowned- he had definitely heard the noise, even if he could barely remember the way it sounded at the moment. The experience still lingered on the edge of his mind.
"Let's find somewhere to rest."
Natori barely allowed room for an answer as he resumed walking, his pace much faster and urgent than before.
-x-
"It must be hard to live in conditions like that for the people who live there now."
The woman's face grew sullen at the exorcist's words, but she hid it quickly enough to where it was noticeable, but where there was no time to dwell on it and inquire.
"It must be."
"What happened to all the people who passed away?" The boy's curiosity grew with every tale along with a gnawing sadness.
The woman's face twisted into the same expression once more. Her next words woven carefully, as if she were concerned about saying something wrong.
-x-
Time was something that was hard to keep track of in the dark, in the fog. The trio didn't know how long they had been walking before Natsume spoke, saying that he thought he saw something in the distance. When they walked toward it they saw that it was a lantern hung on the roof of a building.
"Oh my, it's quite late to be travelling in these parts. Especially such lovely looking me-people."
At the sudden voice, Natsume jumped and yelled in surprise. Both him and Natori whipped around to face the voice that came from behind them. A woman, very advanced in age, stood there and watched them through the light of a lantern she held. "I'm sorry to have startled you. Oh dear!"
"Please, there's no need to apologise," Natori spoke to ease the tension that had built inside him. "We're just a bit tired from our travels."
"Why don't you stay here?" The woman gestured to the building with the lantern that Natsume had first pointed out. "It's a bit run down but there's room available."
Natori looked back at his companions. They had been travelling all day, so being weary wasn't exactly a lie. Also, with what had taken place near the entrance of the mountain, he would prefer them indoors to think of their next move rather than wander aimlessly in the darkness any longer.
"It sounds like a good idea." Natsume walked over to Natori's side before he turned to the old woman, and bowed. "Thank you for letting us stay."
The woman's eyes seemed to lock on him then. "No no, thank you for the company. Why don't you stay as long as you need."