Sabito spends months with Urokodaki before he comes back with another boy.
He hides behind the man, looking unsure, and Sabito forcibly shoves away memories of Kazuha to greet him with a smile.
Giyuu is amusingly easy to mess with, with the way he takes many things far too literally. That, at least, is different from Kazuha. So is the way he gets back at him, and Sabito can never tell if it's intentional or not.
The two have their disagreements, of course, but they grow close.
Giyuu tells Sabito that he's stronger than he'll ever be. Sabito tells Giyuu that he's the most elegant and fluid swordsman he's ever seen.
"Partners ," Sabito tells him one day. "We'll be partners."
Giyuu stares at him with wide eyes until Sabito shakes his pinky at him. He almost laughs at the bewildered expression that makes its way onto his face as they link their littlest fingers together.
Something shifts after that. It's nearly unnoticeable, at first, but Urokodaki relaxes some. He starts putting them through drills that have them working back to back, or side to side.
Sabito also catches him carving something by the fire, but he always turns away before he can see what it is. He thinks the two things are linked, somehow, though he doesn't learn how until months later.
"The Final Selection," Urokodaki tells them, "Is the final hurdle that you must cross in order to become demon slayers."
And then he puts them in front of a boulder, and he tells them to slice it into fourths.
Giyuu and Sabito share an incredulous look. Urokodaki walks away, leaving them to it.
"Is he alright?" Giyuu asks with furrowed brows, sounding like he's truly asking whether or not the old man has gone senile. Sabito doesn't even bother covering up his laugh.
He's fairly certain that there's some sort of reason for them to be doing this. Maybe more than one, knowing Urokodaki.
That doesn't make the daunting task look any easier.
And they spend weeks hacking at the boulder - not roughly, because they'd rather not be murdered by Urokodaki if their swords broke - until Giyuu gets frustrated enough to be reduced to tears.
It's the most awkward moment of Sabito's new life, and he spends the rest of the day reassuring him to make sure that it doesn't happen again. Urokodaki snorts and calls him a mother hen. Just for that, Sabito makes his dinner portion extra spicy, and relishes in the old man's expression when he gives it a taste.
Sabito also decides that he must be looking at things the wrong way. He's been focusing too hard on cracking the boulder into pieces, like he would've with his electro vision. Instead, he should be relying more on his Breathing.
One day, he lures Giyuu into a fight. The boy looks at him like he's insane, but obliges.
Near the end, when Giyuu strikes down with an increasingly familiar look of determination in his eyes - something Sabito loves to see, but will never tell him about, because he's afraid that the boy will get embarrassed and force his expression to remain neutral - he leaps backwards and crashes down on the boulder himself.
Giyuu stumbles, panting and eyeing Sabito with confusion. Sabito grins as the boulder splits into four beneath him.
Giyuu gapes, then looks happier than Sabito has ever seen him in all their time together. It makes his heart melt.
Urokodaki hands them each a haori and a mask carved to look like a fox. Giyuu looks like he's doing his best not to burst into tears.
Sabito laughs, trying to hide the way his own throat feels clogged, and rubs his knuckles against Giyuu's hair until he squawks indignantly. Urokodaki looks on, and although his face is covered, Sabito can tell he's amused.
The next morning, he and Giyuu set off. As they're heading down the path, Sabito pauses, then rushes back to launch himself at Urokodaki.
"Thank you," he tells the man. "For everything."
Urokodaki breathes, hand twitching on his back. "Brat," he says, voice sounding suspiciously soft.
Sabito grins at him, then runs back to join Giyuu. After a moment, said boy offers Urokodaki an awkward wave that's returned with amusement.
And with that, they head down Mount Sagiri, ready to take on any challenges that may await them.