Kakashi grits his teeth as he races through the trees towards Kannabi Bridge. They could have gotten Rin after, it's not like Obito can possibly track Rin quietly enough to go unnoticed without Kakashi there anyway.
Besides, there's no point in Iwa taking Rin just to kill her somewhere else, so they'll leave her alive. Taking out the bridge is a major attack on the Iwa supply chain, which means a major step in gaining victory for the whole of Konoha, surely one person is worth that, it's just basic numbers.
Kakashi has practically been made the local authority on sabotaging supply stations after the first time. The whole of Team 7 knows how this is supposed to work, they've certainly done it enough times.
Kakashi leaps from the trees and skids to a halt, cursing loudly. He turns back to the way he came but doesn't take a step. No. No, he's not doing this, he knows better that to get suckered into Obito's bullshit. Kakashi is a jonin now.
But Kakashi still hesitates.
It's been three years since the last time he tried, since he was banned from the summoning. He's not even sure if he can anymore with his nin-ken contract. Kakashi takes a deep breath and focuses on the feeling of summoning a person rather than a dog.
A puff and Hound appears, but instead of ANBU gear he's in a jonin green flak jacket, cloth mask pulled up over his nose and a headband slanted over one eye.
"You know what happened, right?" Kakashi asks.
Hound has his hands tucked into his pockets, gaze roving over the area. "Kannabi Bridge?"
"Yes," Kakashi answers and pauses. "You go to the bridge, we need to destroy it. I'm…going after my teammates."
"I'll come with you," Hound says and holds up a hand before Kakashi can protest. "It really won't take long, most of the Iwa are chunin. Just make sure when you find the two, you make a run for it. I'm not protecting Rin and Obito when I need to focus, and you can't afford to at your level."
"I could…" Kakashi trails off and reminds himself this is an ANBU, who technically outranks him and should definitely understand his current level considering Kakashi has now verified that they're the same person. "Fine. Let's go."
Kakashi dives for Obito to shove him out of the way and is yanked backwards from a kunai that just barely skims over his eyelid.
Kakashi and Obito are tossed away from the fight, towards the edges, and Hound body switches, kills two close Iwa with kunai, switches again, kills another, switches again and again and again, turning the entire battlefield into a blur, not quite as fast as Minato but more than quick enough for most of the Iwa to be dead before any of them can take a proper step. Raises a field of bloody water from the ground, sets it alight with white electricity that flares out stuttering shadows as the rest of the Iwa go down.
"Oh," Obito says quietly. "So…that's your…uncle?"
"My future self, as far as I can tell," Kakashi mutters, wiping again at his eye. The blood flow isn't slowing down much but when he peeks out, his sight is still clear. "I can summon him, don't ask how because I don't know. He's an ANBU."
"Yeah, well, I bet my future self is pretty cool too," Obito grumbles. "Wait, if he's ANBU, why isn't he dressed in the uniform?"
Hound calmly crouches down to steal a pouch of kunai from a dead body and stands up again as he secures it to his belt. "I got kicked out, for being in ANBU too long."
Obito and Kakashi stare because now that he's not moving at a blur, they can see he's raised his headband to reveal a Sharingan.
"Is that…yours?" Obito asks hesitantly in confusion.
"It's yours," Hound corrects. "You gave it to me, since I lost mine trying to protect you." He nods towards Kakashi and the still rather profusely bleeding cut over his eyelid.
"You know what? That is something I would do," Obito admits.
Kakashi frowns at Hound. "Why are you answering all of Obito's questions so eagerly? You didn't even answer the Hokage, and you blatantly ignore me half the time."
Hound is already moving off.
"Why are you being nice to me?" Obito asks sceptically as he trots after Hound. "That does seem odd for a Kakashi."
"Because I have your eye in my face," Hound deadpans.
Obito gasps as he turns to Kakashi. "Bakashi, you have to be nice to me if I give you an eye!"
"I would rather just be blind, Ahobito!"
Hound keeps a death grip on Kakashi's and Obito's collars, Rin tucked behind him, while they stand at an appropriate distance away as the cave collapses into itself.
The kids are still frozen at the memory of Hound's killing intent pressing down on their shoulders, of watching half a dozen Iwa-nin kill themselves because they made the mistake of looking into a fully developed Sharingan wielded by an incredibly efficient shinobi who doesn't have time to waste pretending that it was ever going to be a fair fight.
"We should get to the bridge," Kakashi says quietly.
Hound blinks, slow, and his Sharingan slides shut. He dismisses himself in a puff of smoke.
"Who was that?" Rin whispers. "Why did he look like…"
"That was older Bakashi," Obito says, giving himself a shake to try and get rid of the feeling of Hound's killing intent. "With my fantastic eye of course. That Sharingan is all me. I probably taught him too."
Kakashi rolls his one open eye as he turns and starts herding the other two towards the bridge. "Considering I was supposed to lose my eye and you give it to me today, that means we both start from scratch."
"Oh!" Rin says. "Kakashi, wait, let me fix all that bleeding. And Obito, congratulations for activating your Sharingan."
"Do it later," Kakashi dismisses. "The fighting was loud, people are probably coming."
Obito blinks. "Wait, what do you mean I activated – oh shit I have Sharingan!" Obito widens his eyes even more, staring around at everything.
Kakashi glances sideways at him. "Did you not notice? It triggered when Hound was putting out killing intent."
"Man, older Bakashi is my favourite Bakashi."
Twenty minutes later as Rin is kneeling beside Kakashi, cleaning out his wound and stitching it back together, Obito leans in.
"Hey, can you swap our eyes?" Obito asks Rin.
"Idiot," Kakashi scoffs.
"Um," Rin begins. "I…can?"
"We're not swapping," Kakashi snaps.
"But think about all the cool shit we can do if we both have one!" Obito cries. "I mean clearly I don't need two if Hound can do all that with just one! And think about you, all your big brain energy, now with my cool Sharingan in your face."
"Yeah, and how's that going to go over with the Uchiha?" Kakashi points out.
"Hound still has his so clearly they didn't put up too much of a fight," Obito tries. "He was ANBU, even. Come on, it'll make you so much stronger, he could use your full Raikiri and everything."
"Then what are you getting out of this?" Kakashi demands.
"Every time you do something cool I can say it's because you have my eye!" Obito cackles.
Both Kakashi and Rin give Obito a deadpan stare.
"Okay, fine," Obito sighs. "Look, you had to save me so many times -not even just today but like a whole lot since we've known each other- and Hound is the one who activated them anyway and you know…I never did get you that present when you made jonin. I just think I'd be cool, to share." He looks away and mumbles, the words 'best friends' and 'friendship eyes' barely audible.
Kakashi looks away as well, a bit of pink blush peeking out from under his mask.
Rin claps her hands together. "We say Iwa wanted to see if a Sharingan could be transplanted so it's technically not our fault."
"Rin!" Kakashi cries in shock.
"That's brilliant!" Obito cheers.
Minato stares down at the three, Kakashi with one eye closed and Obito with mismatched grey and black, Rin trying to look innocent.
Minato only smiles. "You know what? I'm just glad you're all safe."
After recovering from chakra exhaustion but feeling incredibly satisfied the younger Obito isn't dead, Kakashi finds himself at the memorial stone like usual, fiddling with the pockets on his jonin flak vest and staring at Obito's name.
He stops himself from taking out Icha Icha like muscle memory wants him to and instead shoves his hands into his pockets. He stands there for a long time, putting his thoughts together before he finally starts talking.
"Hey," Kakashi murmurs. "So, I got summoned again. Turns out time flows pretty parallel, considering I ended up at Kannabi Bridge…"
In Ame, Obito listens with literally one ear as Kakashi talks, not because Obito cares or anything it's just that Kakashi is one of Konoha's lead operatives so whenever Konoha makes a move it'll be with Kakashi first so really this is just information gathering…
What did Kakashi just say?
"…and I forgot how little you were," Kakashi finishes with. "You and Rin. You were both bigger than me back then but now it's so easy to throw you out of danger – which happened a lot, I forgot how allergic to dodging you were. No, it does not make you cooler to take a hit head on."
Kakashi stops and scans the other names again, knows them all by heart anyway.
"Three more years until the Sanbi happens," Kakashi says. "I hope my younger self calls me again."