Chapter Text
Mitsu wanders the halls of an abandoned building alone.
The second day of the Goodwill Event had gone about as well as she’d suspected. Her peers were angry that she refused to fight Gojo again and they were all laid out by him in the individual battles. Because the Tokyo students are at a numbers disadvantage—fewer students in their second and third years by a wide margin—rules state that the matches have to be a ‘go until you lose’ style.
Starting with Gojo meant that everyone on the Kyoto side lost and no one from the Tokyo school even got a chance to fight.
Mitsu had caught a whisper of disappointment coming from Haibara’s mind before it was immediately replaced with the thought that at least he’d been able to see some of the others’ techniques before Gojo-senpai had beat them. He was quick to share this fact with Nanami aloud before Mitsu left the battlegrounds, and the headache-inducing swarm of many voices, behind.
Reaching out, she lets her fingertips trail along the wall. It’s interesting that there are so many buildings that went unused, in both the Tokyo and Kyoto schools. Were they always so empty? Or did jujutsu society used to be large enough to fill it all?
Gojo’s cursed energy spikes behind her and Mitsu pauses. There's a temptation to run, to hide somehow, but where could she go that would be out of reach of the Six Eyes? Even if she knows it’s a fool’s errand, a part of her wants to give it a shot. If she separated from Hachi, she could try to limit her cursed energy enough to keep him guessing until they left the Tokyo school tomorrow…
Her brother shudders in the back of her mind and she discards the thought. Letting Hachi out is risking him to die by Gojo’s hand, which is unacceptable.
Footsteps echo down the hallway, and she stops completely, letting her outstretched arm fall to her side with a sigh.
“Gojo-senpai, to what do I owe the pleasure?” she asks, looking over her shoulder at him.
He smiles and it’s not with kindness, all sharp edges and ruthlessness housed in those crooked lips. “I just wanted to have a little chat with my little kohai! You basically ran off after the last battle.” He walks up, his height making it easy for him to loom over her. Mitsu turns around to face him completely as he slouches so they’re almost face to face. Her reflection looks back at her from his round black glasses, giving no hint as to the emotion that’s hidden in those blue eyes beneath the glass.
Not that Mitsu needs to see them in order to know his feelings. No, even though Gojo’s cursed energy is remarkably controlled, his thoughts aren’t, and they're currently on a rant, angry and upset that she has taken away his complete defeat by refusing to even try.
“We both know you would have won against me,” she says, focusing her gaze on the middle of his forehead rather than to see the reflection of her own rather flat expression. “There wasn’t a point in trying.”
“Nooo?” he drags out. “Just wanted to savor your win without letting me settle the score, hm? Seems pretty selfish to me!”
Her brown eyes dart down to reflexively look at him. Her vision is tinted yellow from her own round sunglasses but unlike his, they don’t block her eyes from view. Mitsu folds her arms. “I didn’t want to do it yesterday either, but I was forced. Beating you like that gets me nothing.” Turning sharply, her shoes make a loud squeal as she says, “Have a nice day.”
“Beating a special grade gets you nothing?” Gojo repeats mockingly playful. “That’s a shock!”
“I’m also a special grade,” she points out tonelessly as Gojo falls into step beside her.
“But I’m the strongest,” Gojo informs her raising a pointed finger in the air. She glances at him from the corner of her eye. “So that’s not nothing. And your special grade status is only because of your curse, which doesn’t count.”
Mitsu sighs. “Look, without him I wouldn’t have been able to defeat you anyway so—”
“How did you beat me then?” Gojo interrupts, crowding into her space. His cursed energy lashes out and she stumbles into the wall with the force of it. “Explain it to me.” He puts his arm out, caging her in with the long line of his body as she presses her back against the wall wanting to create space between them.
It’s a scare tactic and while she’s not scared, she is uncomfortable. Gojo is only annoyed, not truly angry—at least, not yet—but while he doesn’t intend to hurt her, he isn’t above scaring her to get her to talk, his thoughts tell Mitsu.
She puts her hands out trying to push him back a few inches and they stop in their tracks as they run into Infinity. Gojo smirks down at her and Mitsu rolls her eyes.
“How about we make a deal?” she offers and his grin widens into a smile of victory.
“What kind of deal?”
“A binding vow,” Mitsu says seriously and watches with a small amount of joy as his smile drops right off his face and his mouth opens with surprise. “I’ll tell you if you promise me something.”
“Now, bringing out a binding vow is pret-ty serious. I can’t just agree without knowing—”
“I want you to promise not to harm or kill my brother, ever,” she interrupts, tilting up her chin.
Gojo is silent for a long moment, his mind puzzling this out before he grins. “You made your own binding vow with him, is that it?”
“Yes,” Mitsu answers without hesitation. “While I’m alive, he won’t hurt anyone unless I allow it. If I die and he doesn’t, then he’s free. If I’m not around to temper him, at his heart, he’s a curse so he’ll hurt people, that’s just the way it goes.”
“And sorcerers will hunt him,” Gojo finishes. Mitsu nods. He hums thoughtfully. “Why do you want me to promise this? What does it matter?” He reaches up to push down his sunglasses just enough to peer at her over the frames, the endless blue of his eyes searing through her.
She smiles without joy. “You’re the strongest. Against you, he’ll die. Anyone else? At least there’s a chance at him walking away.” Mitsu doesn't add that those chances are remarkably lowered if Geto went after him, but she doesn't have to. Gojo knows that well enough without her saying so.
Gojo blinks at her before he bursts out laughing. “You’d really let people die for your brother’s sake? A curse?”
“I already lost my brother once. He's just a shadow of who he once was but even still, I don’t want that shadow to disappear if I can do anything about it.”
Gojo finally takes a small step back and she relaxes just a little, not quite so plastered against the wall. He regards her calmly before sticking out his hand.
“Okay then, if that’s all,” he says, his glasses firmly over his eyes once again but he lolls his head in such a way that lets her know he’s rolling his eyes even still. Already he's thinking ahead, planning out who exactly can be trusted to go after her curse brother, if it ever comes to that. Geto is, unsurprisingly, at the top of the list. Just because he vows he won't harm her brother himself, doesn't mean he can't help make plans for someone else to do it.
Regardless, Mitsu knows this is the best she's going to get. Grimly, she accepts his hand and feels the way the vow crawls over her, and she clenches her teeth against the way it feels creeping and wrong, like hundreds of spiders walking over her skin, everywhere and nowhere all at once.
Shaking off the feeling Mitsu barrels into her half of the deal.
“Your Infinity stops anything right?” she asks.
“Well, clearly not everything,” Gojo jokes.
Mitsu shakes her head. “Everything. It can even stop gravity because there’s a formula for it. There’s math or something involved.” Though she didn’t know much about it before, Gojo’s thoughts once she brings it up are enough for her to get the gist. “If you fought Onii-chan one-on-one you’d beat him. He’s a curse, which means he has a body and is something that obeys the laws of math or physics or whatever.” His mind is a jumble of things she doesn’t understand so she pulls out the only thing she does. “Zeros and ones. But when we’re combined, Onii-chan’s arms aren’t his physical ones. You know my technique?”
“I know his,” Gojo corrects. “Psychokinetic, isn’t it?” Her heart skips a beat, and she purses her lips. Generally, people think that she has what is truthfully her brother’s technique and Mitsu is happy to let them believe that. Six Eyes isn’t a joke, it’s almost disheartening to discover.
“Yes,” she confesses. “So usually that just means moving things with his mind, creating force fields and such.”
“But?” Gojo asks, waving a hand around, already bored of her explanation.
“But when we’re fused, he can push out a pair of limbs with his mind. They aren’t ‘real’ in the way that objects are real, or how his arms usually are when he’s separated from me. When his hand touched you, it didn’t hit Infinity because it wasn't really there. They’re part of his mind, in a way. Or his soul I guess you could say.”
Gojo hums, pushing a finger to his chin and tilting his head. He believes it makes him look cute and Mitsu tries not to let her eyebrow twitch as he thinks that.
“I can buy that I guess,” he finally allows. “But why did it knock me out? That wasn’t him. It was you.”
She clenches her fists. “I want to add another thing to our vow. I tell you what my technique is if you agree to never tell anyone else what it is unless you have my permission to do so.”
One white eyebrow raises before he makes a disgruntled face. “So many rules!”
“That’s my offer, take it or leave it.”
He shoves his hands into his pockets, impatience radiating from his mind. Gojo has gotten the information he’d come for, everything else is just extra and he’s ready to leave.
“I can just figure it out myself,” he warns, voice cold. “My eyes are good at that.”
She swallows, mouth suddenly dry. Quickly, Mitsu tries to figure out something else that would be enticing enough. She needs this. Jujutsu society isn’t kind, the Kyoto school has taught her that. If she ever needs to leave, ever needs to have the upper hand against her peers if they should become enemies her trump card has to be protected.
“You’re bored of the conversation,” she says at last. “You’re thinking about bothering Geto-senpai though you suspect he’ll brush you off like he has been lately. He’s always so busy nowadays, ever since you both became special grade sorcerers. Yet somehow, he always makes time for Haibara, which makes you bristle on the inside. Why doesn’t he pay attention to you, the strongest and best? But Suguru has always looked out for the weakest, isn’t that right?”
He moves so fast that Mitsu doesn’t even see it, but she feels the wind as he displaces the air by her head and punches the wall next to her. From the sound alone, she’s certain there’s a crater in the shape of his fist spiderwebbing cracks into the plaster.
“Telepathy then,” he all but spits, anger practically oozing out of his very pores. “So that’s how you got me to sleep.”
Hachi stirs within her, protective as always, but she pushes him down. Steady. This is the important part.
“I can teach you how to protect your mind,” Mitsu offers and doesn’t flinch from his gaze, heavy even through the dark lens. “If you promise to keep my technique a secret.”
Gojo frowns and thinks about it. It’s a back and forth with plenty of Stop listening in!’s thrown in before he makes a decision.
“Ugh, fine.” He straightens and his body language is the picture of annoyance. Another chain gets added to their vow, like the ringing of a gong. “How?”
Mitsu shifts slightly. “Have you ever heard of a ‘mind palace’?”
He tilts his head, and the answer is there, hovering in his mind. Heard of it, yes, know what it really means? No.
“It’s not just ‘imagining a building'," she quotes from his thoughts. "It’s a place to store memories or information by memorizing where you put things. So, create a structure in your head, it can be anything. Your childhood home, a museum, whatever.”
Gojo thinks this is stupid and Mitsu sighs at his poor attempt, half-formed and barely concrete. “I can’t teach you how to shield your mind from me if you don’t take this seriously. Pick a place you know well.” At the memories that he shifts through, the coldness of home, she tacks on, “Somewhere you like, preferably.”
Finally, the jujutsu college springs up in his mind and she’s relieved. “Perfect. Picture yourself walking to what you gauge to be the middle of it. Close your eyes if it helps.”
“Close my eyes if it helps,” he says, mocking and nasally. Mitsu taps her foot and she can hear the echoing tap in his thoughts, a second after she does it.
“Your eyes are still open,” Mitsu points out, used to the slight delay that comes with seeing an image and a mind processing it. Finally, he takes the hint and closes them.
It takes a little bit for him to do what she says, and they go back and forth for a few minutes until his mind’s eye version of himself is standing in the middle of the school.
“Okay, now what?” Gojo asks when the image finally doesn't break after a few seconds.
“You can wrap Infinity around anything right?”
Gojo makes a grunt of agreement.
“Wrap it around the school.”
Another white brow rises but right as it smoothes back down, the endless stream of his thoughts is suddenly cut off, as if a curtain had dropped over them.
Mitsu smiles. “You did it! That’s perfect!”
“What, really? That’s it?” He sounds aghast. “I could have done that myself!”
She shrugs, unashamed. “Most people wouldn’t have a reference like Infinity, it takes them a lot longer to figure it out.”
Gojo scoffs. “That’s because I’m the best,” he says, with absolutely zero shame.
“Mmhm,” Mitsu halfheartedly agrees. His control wavers and she can hear just the slightest bit of his thoughts before the curtain adjusts. There’s a headache pulsing behind her left eye, and she longs to escape towards her dorm. There are a few key bits of information that she’s left out.
Normally, she doesn’t read people’s thoughts all the time. Usually, she picks up emotions at most. But listening in on people’s minds? It’s distracting at minimum, and leaves her with a killer headache at worst. Mitsu only does it in new situations or when she really needs it. But Gojo doesn’t need to know that. Nor does he need to know that if she wanted, Mitsu could touch him and force her way into his thoughts. Most people don’t build a strong enough defense. Even with training, she can probably break down his mental defenses.
But then again, it is Gojo Satoru. Perhaps he would be the exception to the rule. Though Mitsu hadn't heard of him before she joined the Kyoto school, plenty of people regarded him as something special, even if they disliked him.
And besides, Mitsu not knowing him beforehand isn't a surprise, given her upbringing.
“Annoying,” Gojo says with venom, breaking her from her thoughts. “Yet another thing I have to run all the time. Well! This has been fun! Make sure to tell me if my barrier ever goes down, okay?”
He waves a hand over his shoulder as he begins to walk away. Mitsu stares after his back with confusion. Run all the time? Tell him when it goes down? Gojo must mean whenever they see each other, which should be infrequent. “Why would you run it all the time if you’re rarely going to see me?” she calls after his retreating back.
Gojo turns, now walking backwards, hands shoved into his pockets. “Hmm? Oh, I’m going to go tell Yaga to switch you to this school. Why would I make a binding vow with someone I would rarely see? That would be a waste! You don’t like it anyway, so it’s not a problem.”
Mitsu’s brows furrow at his total confidence. “I don’t… but how would you know that?”
He snickers before he turns back around. “A certain kohai let it slip that you might be mistreated by our sister school!” he announces loudly to the air, the words echoing back to her. “So I figure, why not transfer here? It'll be better, not so many closed-minded people. I won’t go easy on you though, so make sure you start fighting back from here on out! Or else you won’t ever get close to my level. C’ya!” Opening the door at the end of the hall, Gojo gives her one last jaunty wave before disappearing into the light.
Mitsu waits a few seconds until she’s certain he’s gone before she takes a step back and lets gravity take her. Her shoulders hit the wall and she follows the line of it down until she’s sitting on the floor, staring blankly without seeing anything.
A certain kohai? Nanami is the only one who she’d even discussed the bare bones of her situation with. Did he seriously mention it to Gojo? Why? Was it just something that came up in conversation? She doesn’t think so. Nanami’s thoughts had made it clear that he at most tolerated Gojo’s presence but wouldn’t seek it out and certainly wouldn’t have a casual conversation with him if he could help it.
Maybe he was talking to Haibara about it and Gojo managed to overhear?
“Arghhh,” she whines, burrowing her face into her knees. Hachi pokes at her, concern radiating. “Nothing, nothing, I just. Nanami only called me cute I don’t need to get a crush on a guy from just that! It’s not like he even said it to my face or anything!”
Hachi’s consciousness dims, his interest waning quickly as he realizes she’s not in any danger.
“The one time someone manages to shield their thoughts and it’s the one time I want more information,” she grumbles aloud, wrapping her arms around her legs. “It can’t be when they’re thinking R-rated thoughts about the total stranger sitting across from them, noooo.”
Propping her chin on top of her knees, she hums loudly, considering. “Moving here wouldn’t be so bad though, would it, Onii-chan? What do you think?”
There’s an answering swell of emotion that Mitsu has come to understand is Hachi’s version of a mental shrug. Indifference at its finest.
“Except for Geto,” she adds, sneering at the thought of the sorcerer. His curse manipulation is something to constantly guard against, frustrating though that might be.
Hachi digs into her thoughts and seems to realize finally what she’s referring to. He doesn’t always listen when she talks to people, instead, he prefers to sift through the memories after the fact, as if her emotions that layered over the memory made it make more sense to him.
You’ll get stronger, her brother says and even through their mental connection, it sounds gravelly, in a way that it never was when he was human.
“Suppose that’s true,” Mitsu allows.
Then it’s a good choice. Take what you can get.
Wrinkling her nose at the thought of more training, she gets to her feet, wiping off the back of her thighs and ass.
“If you think it’s a good idea, then we’ll do it,” she says. Hachi swells with approval.
It’s you, it’s me, her brother starts, the connection between them shivering with pride.
“It’s us,” they say together.