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Zenitsu clutched his sword tight in his dominant hand. Although not in a battle ready stance befitting that of his breathing style, his eyes were wide as he scanned the trees and his ears were receptive to the sounds of the wind whistling through the trees. As the leaves rustled behind him, Zenitsu felt his muscles tense up and his breathing deepen and quiet.
Like a serpent coiled to strike, Zenitsu was tensed and at the ready to swing his sword.
Above him, the sun was at its highest peak. If it were any other day, Zenitsu and the rest of his fellow Demon Slayers would have stopped for lunch. At that very moment, Zenitsu felt his stomach roll in dismay, as if sensing that its daily serving of food wasn’t going to be given its usual scheduled serving.
Zenitsu could relate.
Nothing about today could be considered “usual”.
For one, when the Demon Slayer trio had woken up from their makeshift camp in the midst of hiking up a mountain, Inosuke had been uncharacteristically silent and contemplative. For a person who was used to having his eardrums blasted by the boar child’s obnoxious antics, the blond had been relieved for the sudden reprieve. Despite that, however, it was Tanjiro who had expressed great worry and concern over Inosuke’s taciturn nature.
“Is something troubling you?”
The redhead had placed a cautious hand on Inosuke’s broad, tanned shoulder. It was a gesture of affection, Inosuke must have realized, because he didn’t shrug away from Tanjiro’s touch. Instead, the boar child scratched his chin and faced Tanjiro, the blank eyes of the boar mask seemingly even more unsettling and blank than usual.
“I want to grow stronger, Gonpachiro.”
As always, Tanjiro’s friendly smile had degraded into a grimace at the butchering of his name, but the redhead had managed to nod slowly in understanding.
“Don’t worry, Inosuke! As long as we practice and train—“
Inosuke interrupted with barely a thought for Tanjiro’s inspirational speech. “No, Tontaro! I want to grow stronger not by training,” the boar child puffed up his chest and swung his swords high up into the sky so that the sunlight glinted off the serrated blades, “I want to fight you both!”
Zenitsu rolled his eyes.
“Didn’t you learn from the first time we met?” Zenitsu leaned his back against the trunk of a tree, already too tired from this inane conversation. He regarded Inosuke with an exasperated, but fond gaze, but continued, “We Demon Slayers can’t fight each other. Why would you want us to fight anyway?”
“Hahahah! But how are we to get better if we don’t constantly practice! Fighting with our different styles can teach us new things!” Inosuke slung a muscled arm over Zenitsu either oblivious to or purposely ignoring his friend’s groan of disgust. “Pankitsu, fight me!”
“Tanjiro, please tell Inosuke that—” The blond found himself stuttering to a halt when he realized that the one person he thought would be sane enough to back him up actually looked like he was giving Inosuke’s spiel some thought. The blond groaned and pushed himself off the tree to confront his first friend. “Come on, Tanjiro! We’re supposed to head into the next town over within the next few days!”
Tanjiro looked troubled for a second before a bright grin shone on his face.
“Instead of actually sparring with each other, we can make it a race!”
Zenitsu’s ears pricked up at that.
A race?
Not only would that get them to their next destination faster, but while his comrades would be competing against each other, Zenitsu could easily make it down the other side. After all, thunder breathing style was all about speed and efficiency. So long as he remained focused, then Zenitsu would surely win!
After all three agreed, they decided on some ground rules.
No major or threatening wounds.
They could go all out with their styles and special abilities so long as the first rule was adhered to.
The first one to reach the bottom of the mountain on the other side wins.
Within the next half hour, Zenitsu basically blasted through the competition. Tanjiro and Inosuke, the true warriors they were compared to him (or so he thought), were far more focused on using their abilities to battle each other. If Zenitsu wanted, he could have stayed behind to watch to see how their respective styles fared against each other.
However, the blond was a realist and wanted to win.
So, down the mountain he went, fully aware of the sounds of sword chasing against each other accompanied by the sounds of grunts of pain and whoops of victory that rang through the air every so often. It wasn’t like Zenitsu didn’t want to fight (a part of him did) but he wanted to stay true to his objective.
Besides… they had yet to decide on what the prize was going to be.
Finally, when Zenitsu stepped onto flat ground, he allowed himself a small smile as he dropped flat to the ground.
Victory! How sweet did it taste upon his tongue.
As the blond rested underneath the shade of an ancient tree, he tried to rest and quiet his breathing that had become somewhat labored since he had run all that way down the mountain. However, before he could fully rest his eyes, his ears began to prick with a sound that he was all too familiar with.
Footsteps.
At first, Zenitsu didn’t seem to find anything wrong with it.
And then—
He realized that the footsteps were accompanied with… something rumbling? Yeah, it sounded a lot like something was… rolling down something?
Like thunder… rolling thunder?
With the speed and agility that not many people would associate with him, Zenitsu jumped up to his feet and unsheathed his sword. Although his eyes were not as sharp as his ears, he kept his gaze focused at what appeared to be a dust storm cascading down the mountainside.
Zenitsu’s warm brown eyed gaze narrowed.
If the footsteps paired well with that cloud of dust (which it did thanks to his ears), then Zenitsu had to wonder… What did those two idiots do?
Zenitsu stood stock still, his breathing nearly silent for a second.
And that’s when all hell broke loose.
Surprisingly, it was Tanjiro who came barreling down the mountain first. When the redhead saw Zenitsu, there was a brief flash of a smile on his face before it became grim.
“Get out of the way! Inosuke and I accidentally dislodged a boulder and—!”
Inosuke came tumbling next, his boar head somehow still resting tightly on his head.
“Monitsu! We’re gonna die! Hahahaha!”
As the pair of Demon Slayers ran past Zenitsu, the blond stood tall and straight, his hand twitched upon the handle of his sword.
His eyes closed.
And as the boulder bore down on him…
Zenitsu could hear the shouts of his teammates scream for him to move, to turn right or turn left…
Yet—
He stood still, his eyes closed, and he shifted into first stance, and then—
“Thunder Breathing First Form,” his eyes glowed somewhat dimly amid the contrast of the sunlight around him, “Thunderclap and Flash!”
And with that, the Thunder Breather slashed forward—
—and into the boulder, causing it to fall apart in half.
As Zenitsu sheathed his sword, he could hear the awed sounds and gasps of awe from his fellow Demon Slayers.
“That was so awesome, Zenitsu!” Tanjiro cried among the petulant cries of Inosuke claiming that he could have done the same. He came forward to embrace Zenitsu, almost as if the blond had been harmed in the maneuver. “I couldn’t have done that!”
The blond’s cheeks warmed at the compliment; on his tongue, he ached to say that he didn’t deserve such kind words, but something else came out.
“Didn’t you say that you sliced through a giant rock before the Final Selection,” Zenitsu asked him. “Why didn’t you do just that?”
Tanjiro blinked, his eyes wide and his cheeks just as red as his hair. “Oh… It was going too fast, though!”
Zenitsu resisted the urge to smack his palm against his forehead.
“Whatever… Can we go now? I’m going to have the both of you treat me to a nice meal at the next shop we come across as a reward for winning!”