"Get him," Fushiguro yelled, looking at Demon Dog. The shikigami didn't need verbal instructions, not in the way a real dog would, but Fushiguro often used them anyway.

The dog bounded away, doing its best to avoid the spikes raining from thin air, as Fushiguro watched from behind the barrier.

He didn't usually fight like this. Most shikigami users hung back and let their creatures do the work for them, but Fushiguro was wary of allowing that much reliance on his shadows. He usually joined them in battle, exploiting the weak spots they exposed on his targets, and he wasn't used to standing back and watching.

Something in the air shifted, and Fushiguro looked up to see the air at the top of the train car condensing to form a slight mist.

"What's that?" he asked automatically, although he wasn't sure who he was asking. He was fairly sure Gojo was long past the point of answering questions.

"Poison," Itadori said, with a certainty that made Fushiguro suspect the answer had come from Sukuna. "More poison."

Fushiguro resisted the urge to take a step back. Gojo was clearly still holding infinity, or they would all be dead. The poison mist…couldn't get through, right?

There was a moan from Gojo, as if he could tell what Fushiguro had been thinking. "Infinity…."

The rest of his sentence was lost as Gojo began to cough again, a horrible hacking sound. Fushiguro didn't want to take his eyes off his shikigami, but it sounded like Gojo was minutes at most away from passing out, or worse.

"Hey, don't try to talk," Itadori said. He sounded surprisingly calm, as if he did this every day.

Fushiguro heard a small, wet splat as Gojo coughed something out, and then he was trying to speak again.

"Can't…block…air."

It took Fushiguro a second to understand what Gojo meant. And then, he started to realize that he felt a little off, and that the inside of the barrier was filling with the same sort of mist that hung around the rest of the room.

Immediately, Fushiguro started trying to breathe less deeply, so he would get less of the poison into his lungs. He didn't need long to take out the curse user with Demon Dog, but if he passed out, Demon Dog would disappear. Gojo was clearly in no shape to take out the curse user himself, and Itadori didn't have anything long range, so that would put them in pretty bad shape.

Fushiguro silently urged Demon Dog forward. It didn't matter if he got hit now. It would take a lot of spikes to do enough damage to make Demon Dog vanish, and if that happened Fushiguro would just need to pull out another shikigami. It was way too late for Demon Dog to try to dodge.

Behind Fushiguro, Gojo was coughing. He was already so sick, and the poison mist couldn't be doing him any favors. It sounded like he couldn't get his breath back. It sounded like he was going to die.

Demon Dog was slowing down as he approached the curse user. The poison was taking a toll on the shikigami too. But the curse user had already shown so many techniques - surely he couldn't have anything else up his sleeve. And if Demon Dog could survive the spikes, and the poison mist, then….

"Um, Fushiguro?" Itadori asked. "Is your dog going to be okay?"

"Yes," Fushiguro said. "The poison won't be enough."

Fushiguro barely had enough time to hope that this was true before he saw Demon Dog crouching. A fraction of a second later, he sprang. Then the curse user was on the ground, and there was blood everywhere.

The poison spikes dissolved as if they'd never been. The faint lightheadedness Fushiguro had been feeling after starting to breathe in the mist remained, but he couldn't see the mist itself anymore.

"Wait!" Fushiguro yelled as his dog started to tear into the curse user. "He's a human. Let me restrain him."

He was already summoning Toad as he spoke. An instant later, the curse user was safely stored away in Toad's mouth. Fushiguro didn't really know what was supposed to happen with him now, but he supposed that wasn't for him to decide. Now that the curse user had been defeated, hopefully Gojo would be able to heal. This definitely sounded like the sort of thing that a teacher should be figuring out, not a student.

Fushiguro turned back towards Gojo and Itadori. Neither of them had been watching him. Gojo was curled on the ground, an arm wrapped loosely around his midsection while the other hand covered his mouth. Itadori was looking down at him with wide, scared eyes.

"It's done," Fushiguro said, and then when Gojo didn't react, he repeated it a little louder.

"Mr. Gojo!" Yuji placed a careful hand on the teacher's back. When Gojo didn't react, he shook him a little. "Fushiguro did it! We're safe, and you can drop infinity. Can you...you need to heal yourself!"

Gojo thought Yuji was talking to him, but it didn't seem all that important at the moment. He was far more focused on his lungs, which had stopped working. He struggled to draw in a breath, and was rewarded by a thin wheeze that caused unimaginable agony to shoot through his chest.

"Mr. Gojo! The curse user is down, you're safe! Aw, man, I really need you to respond to me…."

Gojo heard the echoes of the words, but he couldn't force meaning through them. A hand was on his back, and that hurt too, but it was okay. Gojo had to keep infinity up, and the hand was why. Yuji's hand. He was keeping Yuji and Megumi safe.

"Mr. Gojo…."

Yuji sounded miserable now, his voice thick with fear, and even through his own pain, Gojo recognized it. He didn't want that. Not for his students.

"Drop infinity." That was Megumi. He sounded scared too. "Mr. Gojo, you have to heal. We're safe. Drop infinity."

"He's right, Mr. Gojo. Drop infinity, please."

Drop infinity. The words cycled through his head until they crystallized into meaning, and even then, Gojo wasn't sure he understood. Infinity was his job, he was supposed to hold it until he…passed out, or died, or stopped breathing, and then beyond any of that. He was keeping the students safe.

Both of Yuji's hands were on his back now, and Gojo moaned as his body shifted. Pain lit up in every nerve ending, and the nausea came roaring back.

"Heal yourself," Yuji shouted. "We're safe, I promise! Fushiguro won!"

In the end, it was Yuji sounding scared that filtered through the fog of pain. Gojo couldn't lose himself in the agony and leave his student sounding like that. Without really understanding why, he forced his eyes to open, and the information from Six Eyes flooded his brain.

Megumi and Yuji were nearby, tense and nervous balls of twinned cursed energy. There was more cursed energy in the corner, but before Gojo could panic, it resolved itself into the outline of Megumi's shikigami.

The curse user was gone.

They really were safe then. And Gojo needed to heal.

Relaxing infinity was difficult, almost painful, like standing up straight after you'd been crouched for too long. But once it was gone, the RCT kicked in pretty much automatically, and he felt such overwhelming relief for a second he thought there was a chance he would cry.

It took him less than five seconds to heal the damage to his internal organs, his bloody nose, his pounding headache, and his horrible nausea. All of that happened pretty much on instinct. He didn't think he would have been able to describe what he'd actually done, what had actually been wrong. All he knew was that he was alright now.

Nothing hurt.

"Mr. Gojo?" Yuji asked cautiously. "You used RCT, right? Are you…okay?"

Gojo's headache was gone as if it had never been - he was pretty sure he could have even switched back to his sunglasses, if he hadn't lost them somewhere farther back in the train. Slowly, Gojo used a hand to push himself into a sitting position.

"I seem to have been able to heal myself," Gojo said.

"You're not going to die?" Yuji asked.

"I was never going to die, Yuji."

"Um-"

Since sitting up had gone fine, and Gojo really did feel pretty good now, he grabbed one of the train seats for leverage and heaved himself to his feet. He'd been optimistic, but he was rewarded for his efforts by a wave of lightheadedness that almost sent him sprawling again. Gojo swallowed against another small wash of nausea.

"Uh oh," Megumi said. "I don't think the RCT worked."

"The RCT worked, it's just…I can't fully cure myself from poisons," Gojo said. He'd even explained this to the kids earlier in the train ride - so much had happened that he'd simply ended up forgetting. He couldn't actually use RCT to flush poisons from his system. Shoko had told him that it was probably possible, and it was a personal failing that he hadn't yet managed it, but in any case, he just wasn't sure how to do it. He could heal the effects of the poison as they popped up, and eventually, it would leave his system naturally.

Until then, he would apparently have to use RCT pretty often. This poison had been a nasty one. If he didn't watch out, he could end up in pretty bad shape again.

"Are you two alright?" Gojo asked. "There was that mist, right at the end-"

He couldn't see the mist anymore, either on his own or with the Six Eyes, but the effects from the poisoned tea hadn't vanished when the curse user had been defeated, and so he was pretty sure the effects of the mist wouldn't have either.

"I'm safe," Yuji said. "Um, poison immunity again."

"I think I breathed some in," Megumi said. "I was dizzy for a second, but now I feel better. I don't think I got very much."

"We can have Shoko look at you when we get back to Jujutsu High," Gojo said. "Just to make sure you're okay. And tell us if you feel any worse, alright?"

"Yeah, definitely let us know if you start to feel anything weird happen," Yuji said, turning his worried eyes on Megumi.

"I will. Thank you. But I don't think I got that much."

"Where is the bad guy, Megumi?" Gojo asked.

"Toad has him," Megumi said. "Are we bringing him back to Jujutsu High?"

"Probably," Gojo said. He figured the higher ups would want to interrogate him - not that Gojo really thought they'd get anything useful. If he hadn't been working alone, he wouldn't have been alone, and they would have ended up in a lot worse shape. And he hadn't known anything about Gojo's technique that wasn't basically public record - he'd just used the information to lay a particularly clever trap.

"Who was that guy?" Yuji asked, looking at Toad, which was resting behind Megumi looking proud of itself, in a froggy sort of way.

Gojo shrugged airily. "Oh, just some guy."

Yuji looked confused, then vaguely frustrated. "But he tried to kill you. How come?"

"Because I'm Satoru Gojo." Gojo gestured towards himself with one bloody hand, but Yuji didn't seem to be accepting that as an answer. He sighed. "People have been trying to assassinate me since I was…like, five months old, Yuji. This is nothing new. He was just…better at it than some of the others."

"Oh," Yuji said quietly.

Gojo must have forgotten to tell him about that sort of thing. It was sometimes hard to remember that Yuji was so new to jujutsu society, since he'd advanced so well in combat terms.

Megumi, on the other hand, who was far more acquainted with the jujutsu world, didn't look too surprised. Gojo thought he might still look a little worried, but it was hard to tell with Megumi.

"That's enough of that," Gojo said, clapping his hands. Something very deep inside him still twinged if he moved too fast, but he ignored it. He'd almost died from being poisoned, and it was only natural that he was going to feel a bit off until the substance cleared his system. If anything was really wrong, the RCT would take care of it. Megumi and Yuji were probably in slightly worse shape at this point, since neither of them had RCT themselves.

"Megumi!" Gojo turned to his student, taking care this time to move a little slower. "Excellent job beating the curse user! I know you don't like to rely on shikigami alone, but I'd hate for you to forget about the advantage you have in a ranged attack. And…you didn't! Yuji here, and me too, wouldn't have been able to beat him. Thank you."

Megumi nodded solemnly, but the corner of his mouth twitched into a smile.

Gojo was fully intending to praise his student just a little bit more, but he was cut off by the feeling of something in his throat. He coughed, then reached into his mouth and drew it out. Clasped delicately between his finger and thumb, he held a small, pinkish, spongy lump.

"Ewww!" Gojo yelped, then giggled. "That's a bit of an organ, I bet. Pretty gross, huh?"

Neither of the students seemed to want to inspect it, so Gojo flicked it away, off towards the end of the train car.

"Alright, precious students. Let's-"

Yuji hugged him. He moved fast, and Gojo always forgot that he would lose track of Yuji if he wasn't keeping an eye on him. Yuji's arms were around him before he'd even realized Yuji was approaching, and somewhat to his surprise, he realized he'd let Yuji through infinity on instinct.

Gojo stiffened. He had not been hugged in…a very long time.

"I'm glad you're okay," Yuji said. His arms were still tight around Gojo.

It took Gojo a second, but slowly, he started to relax. Being hugged wasn't terrible, he supposed. He could see why other people did it more often, in fact.

A second or two went by, and then Gojo felt another set of arms wrap around him. Megumi? Gojo was shocked. Megumi hadn't even liked to be touched when he was a little kid. Gojo didn't think he'd ever received a hug from him. He was flattered. His students…must have been really worried.

Megumi was involved in the hug for only a few seconds, and then Gojo felt him let go and heard him backing away. Gojo was still in shock. A hug didn't need to be long. Any hug, and from Megumi, was really something.

"I'm alright," Gojo said. He didn't pry Yuji off, even when Yuji continued to hold on for what felt like possibly several minutes. "I'm alright."

Once Fushiguro had taken out the curse user, things had started going much smoother. Gojo had taken down infinity long enough that he could do RCT, and that had helped a lot right away. In about fifteen seconds, Gojo had gone from looking like someone on death's door to someone who looked almost normal. He was still pretty pale, Fushiguro thought, but then again, Gojo was always pretty pale. It was hard to know for sure if this paleness was worse than the usual kind.

He'd needed to run RCT on himself every couple minutes while they waited for the train to arrive in Tokyo, but every time he healed himself, he started looking better, not worse. The conductor had come and found them, and thanked them, and brought Gojo some more ginger ale, and he had started looking a little better after drinking that as well. He still seemed tired though, even after multiple rounds of RCT, and Fushiguro was relieved when he heard the announcement that they would be pulling into Tokyo shortly.

"You're still okay, right?" Itadori asked as they began gathering their belongings together.

"I'm probably better off than you are at this point, Yuji. We're all going to need a visit to Shoko as soon as we get back to Jujutsu High."

"That didn't really-"

"Don't worry," Gojo said. "Like I keep saying, I'm fine."

Itadori's eyes narrowed and he looked at Gojo for a long few seconds. Fushiguro had no idea what was going through his head, but at the end of it, he nodded, and his face relaxed.

"Alright. I'm glad you're okay, Mr. Gojo. How far do you think your infinity could go, if you stretched it?"

Gojo paused, tapping one long finger against his chin. "Hmm…."

"Could it cover the train? Could it cover the school?"

"I've never tried to cover a train. But no."

"Aww. But if you could cover a train, but you weren't on it, how far do you think the train could get before it wasn't inside infinity anymore?"

"Not as far as you would think, Yuji. Infinity isn't stretchy-"

Gojo really did seem better, if he was ready to engage with Itadori about this kind of thing. But Itadori was still hurt, even if he didn't seem to remember it, and Fushiguro was surprised that the wound in his shoulder hadn't started bleeding again during the fight.

"Itadori."

Itadori, who was circling Gojo with an expression of great concentration, and occasionally poking at the newly-reinstated infinity, paused and looked up guiltily.

"Sorry," he said, glancing at Gojo. "I'll…stop-"

Fushiguro frowned. "You're hurt too, Itadori. Your shoulder. Don't move so much."

Itadori blinked at him, looking confused. Fushiguro paused. Should he be more worried about Gojo? The sorcerer had been far worse off than Itadori, even if he seemed fine now.

"You're right, Megumi," Gojo said, shooing Itadori a little ways away. "Yuji, you should be more careful. Shoko will fix you right up, but she can't if your arm falls off or something."
Itadori blanched. "Um, it doesn't look like it will, right?"

"Not now," Fushiguro told him. "But I don't know about if you keep moving it around."

"I'll…be careful," Itadori said, a little more quietly.

"Great idea!" Gojo clapped his hands. "You can be careful all the way off the train, which we can leave right now! We should be stopping shortly."

Fushiguro watched the teacher walk down the aisle, steady as ever, and decided that he had been overreacting. Gojo had looked bad for a moment, that was true, but he was fine now. He was always fine. He should be focused on Itadori, who still looked a little pale, and was likely to reinjure himself unless someone kept a close eye on him.

Fushiguro hadn't realized quite how tense he was until the train pulled into the station and the doors opened on the familiar platform. Even Gojo relaxed a little, his shoulders dropping slightly as he stepped off the train.

"Should I call Ieri?" Fushiguro asked, following his teacher onto the platform. "Sometimes she doesn't take your calls, Mr. Gojo."

"That is…probably a good idea," Gojo said. "But first, ice cream!"

"What?" Fushiguro asked.

"Look!" Gojo said. Fushiguro looked. Gojo was pointing at an ice cream shop in the train station. Then, seemingly satisfied with Fushiguro's lack of reaction, he started walking purposefully towards it.

"Mr. Gojo…." Fushiguro trailed off. He was so surprised by the abrupt plan change that he honestly wasn't sure what to say.

"Don't worry," Gojo said. "I'll buy the two of you any flavor you want. Think of it as a reward! You both did a great job today. And sugar is the best reward."

"Really?" Itadori said excitedly. "You'll buy us ice cream?"

"Mr. Gojo," Fushiguro said, "Itadori is hurt."

Itadori turned big puppy dog eyes on Fushiguro. "But Fushiguro, come on. It's free ice cream. And doesn't it look good?"

"I guess as long as your shoulder is alright…."

"Nice!" Itadori said. "I think Mr. Gojo is right, sugar is the best reward…."

Fushiguro remembered Gojo throwing up into his bag of sweets, and he frowned. "Mr. Gojo, are you really sure you're up for desserts? You were pretty sick."

"Don't worry, Megumi!" Gojo said happily. "I am never too sick for ice cream."

Fushiguro supposed there was nothing he could do, and besides, ice cream did sound good. He trailed after Gojo, and waited patiently as Gojo sampled several different flavors. He ended up getting a cone of soft serve, and Itadori, after agonizing for a moment, got the same thing as Gojo. Fushiguro got a small cup of vanilla ice cream - with things like ice cream, he always figured simpler was better.

"Alright!" Gojo said, leading them over to a bench where they could sit for a moment and eat. "I know we already talked about this earlier today, but I think it is definitely time to go over what we learned! Megumi, you first! What's one thing you learned today since I last asked you? Go!"

Fushiguro was distracted from answering by the sight of Gojo inserting his entire ice cream into his mouth. It was disturbing to watch, but at the same time, it kind of made Fushiguro feel better. If Gojo could eat an ice cream cone like that, he really must be feeling okay. And if Gojo was feeling okay…it had been a long day, but finally, everything was back to normal. They would all be just fine.