Nobody on Taichi's side knew about leylines. That was fine, because some of Kotoko's Yokai did. Guided by the Yokai, the two groups reunited at the intersection of two leylines.
"Shibuya Station? Right here?" Taichi asked, surprised. It was like they were back at square one.
"To be precise, it's pretty deep underground," Kotoko answered. "The Yokai can't enter because of a spell blocking the way."
"Then have the Yokai find a few more passages," Taichi said, shaking his wrist. "In case this place collapses after we defeat the mastermind, we'll have a way to get back to the surface."
"I've already told them to do that," Kotoko said, looking at Taichi with a hint of admiration. "Finding a few more escape routes is a very stable plan."
"Inhale... Exhale..." Yui Yuigahama was doing deep breathing to calm her fear. Yukino Yukinoshita, on the other hand, looked perfectly fine, probably because she had mentally prepared herself on the way here.
"How's the spirit collection coming along?" Taichi asked Kotoko before they entered Shibuya Station. Her Yokai were the main force for collecting spirits.
"We've successfully collected over a hundred thousand spirits. The streets are clean; most of the remaining ones are in more hidden places," Kotoko answered. "I've already instructed the Yokai not to miss a single corner."
As the God of Wisdom for the supernatural for several years, Kotoko was even more meticulous than Taichi had imagined.
"Let's go," Mordred said, resting her sword on her shoulder. "I'll take the lead!" After they met up, Taichi had given his gauntlets back to Mordred. In this situation, Taichi's limited combat ability was useless, so it was better to let Mordred be as well-equipped as possible.
"Then I'll stay behind and protect the Master," Raikou said. She wasn't particular about her position, as long as it didn't interfere with her protecting her Master.
The group entered the subway station in high spirits.
"It's in this direction..." A rat-like Yokai stopped at a point on the subway tracks, tapped the wall, and pointed diagonally downward. "It's about twenty meters down from here."
"Seriously? What about the regular entrance?" Taichi asked, looking down at the rat.
"There isn't one," the rat Yokai replied, shaking its head. "The opponent must have used some kind of spell. Anyway, there's no official passage."
"Then why don't you just dig a hole?" Kotoko asked.
"Princess, it's not that we don't want to; it's that we don't dare," the rat Yokai said, shaking its head in fear. "The Netherworld aura in that place is too thick. If we little Yokai get close, we'll die."
"In fact, if it weren't for the Princess's orders, even being twenty meters away from it would make me want to turn and run." The rat Yokai was on the verge of tears.
"Wait, wait! If even Yokai can die from getting close, what about us?" Yui asked, her face filled with terror.
The rat Yokai, on the other hand, rolled its eyes. "Ma'am, you survived a fog that was much thicker than that aura. Are you really afraid of a little miasma from the Netherworld?"
"Huh? I don't have to be afraid?" Yui asked, bewildered.
"This is a bit of a blind spot for us. How about you explain it to us?" Taichi asked the rat Yokai.
"The fog that appeared on the surface was actually a physical manifestation of a large amount of 'Netherworld miasma'," the rat Yokai explained. "Don't think we Yokai just popped out. We only dared to come out when the 'miasma' was about to dissipate. Otherwise, the first wave of fog would have directly wiped out all of us non-Netherworld beings." The rat Yokai shivered in fear. "Only the Nekomata, who are naturally immune to Netherworld miasma and can freely travel between the human world and the Netherworld, were the first to appear."
"As for the Netherworld aura down there, it's probably about as strong as a slightly diluted version of that thick fog."
"At most, it will just make you beings who have crossed the 'boundary' feel a little unwell both physically and mentally. But for us, it's a terrifying thing that means instant death."
"Wait, what about Kotoko-san?" Yui interrupted the rat Yokai. "She's not like us. She didn't cross that 'boundary' and survive, right?"
"That's why I'm with her," the Nekomata said. It had been crouching at Kotoko's feet the whole time, its eyes glowing green as it stared intently at the rat Yokai.
Squeak! The rat Yokai was startled and scurried away in an instant.
"While I'm not a fighter, I can act as a 'battery' for the Princess to prevent the Netherworld miasma from eroding her," the Nekomata said.
"...Are you the same Nekomata I met before?" Taichi asked, examining the Nekomata.
"I assume you are Taichi-sama," the Nekomata said, looking at Taichi with a strange look. "The Nekomata you saw before was a distant cousin of my great-uncle's third nephew."
These Nekomata didn't have a habit of giving themselves new names. As for the names they had as house cats, they were as important as their "true names" and would not be revealed to outsiders. Of course, Kotoko, the God of Wisdom, was an exception. If she wanted to, she could know the "true names" of all the Yokai under her command.
"Mordred-san, please use your sword to cut down this wall," Kotoko said, tapping the Nekomata's forehead with her cane and looking up at Mordred.
"...We don't have money to pay for this," Mordred said cautiously, knowing that in modern society, damaging public property not only incurred fines but also led to jail time.
"All debts will be handled by the 'Disaster Relief Department'," Kotoko answered. "That's the promise I got before we came in. Besides, even if those people don't acknowledge it later, the enemy is the one who broke the wall. What does it have to do with us kindhearted civilians who are working hard to collect spirits inside?" Kotoko blinked, implying she had plenty of excuses. It was clear she didn't have much faith in politicians.
After getting Taichi's nod, Mordred knocked on the wall to test its hardness and then punched it with her gauntlet-fist. This man-made wall didn't even require her sword; she could make a hole with her fists. After two punches, a crack appeared, and after two more, rocks began to fall, and a hole over a meter high appeared before them. It was pitch black, like a one-way path to the Netherworld.
Yukino Yukinoshita took out two flashlights from her bag and shined them into the hole.
"...Am I the only one who thought to bring flashlights?" Yukino asked, her lips twitching slightly as she looked at the others who didn't move.