Tanjiro was tired.
He'd just finished what was just about the hardest fight he'd had in his life, and his entire body ached, and there was that dumb crow screeching in his ear, and Nezuko really was getting a little heavy (he loved his sister to pieces, but carrying her was exhausting sometimes), and he still had so far to walk before he reached his next assignment. The weather was great, it really was, but Tanjiro couldn't find it in himself to enjoy it. It was hot and boring and utterly uneventful, and with his sore limbs, the day was turning out pretty shitty.
And then he heard the screaming.
He'd reached for his sword initially, thinking someone was getting hurt, or worse, eaten by a demon, but after a few moments he'd looked into the distance and identified two people down the path. Two very small, very loud, very human people. One of them was dressed in a blue kimono, the other in an bright yellow and orange haori, sporting vibrantly blonde hair. Both were yelling.
Ah, Tanjiro thought dryly. Maybe today won't be as boring as I thought it was going to be.
When he got closer, he managed to make out the words of the haori boy, who was crouched on the ground in front of the girl wearing the kimono. It seemed he was screaming 'please' repeatedly, and Tanjiro perked up, intrigued. Something terrible must have happened for him to be so distraught—he should go help. So he sheathed his sword and grabbed the straps of Nezuko's box, breaking into a run towards the pair.
"Please marry me!"
Tanjiro stopped moving.
"I'm going to die soon, you know! Please! I'm begging you!"
"What in the world?" Tanjiro muttered. He'd prayed for the day to get less boring, but this wasn't what he'd had in mind.
The crow on his shoulder squawked and flapped its wings as a sparrow approached, landing on the hand Tanjiro raised for it. Chirping frantically, it nodded back towards the kneeling boy, then turned to look at Tanjiro, bobbing its head. Behind it down the road, the boy continued to clutch at the kimono of the girl standing over him, bawling. "You're the only one for me! Please marry me, please!"
"What's happening?" Tanjiro asked, rather helplessly. The two people didn't answer—he was too far away for them to notice him—and neither did the birds.
This is getting out of hand.
"I'll do something about this," Tanjiro promised the sparrow, which brightened considerably at his words. The crow shifted from one foot to the other, then lifted off as Tanjiro began running again, tossing the sparrow into the air. Reaching out one hand, he seized the boy by the back of his haori and hoisted him into the air. "Can't you see she doesn't want to marry you?!" he shouted, faltering slightly when the boy whipped around, revealing a tearstained face. The girl backed away a little more as Tanjiro shook him several times. "In the middle of the road, too? Do you have no shame?"
Golden eyes stared at him for several long seconds, the drifted downwards. With a yelp, the boy flailed one dirty hand at Tanjiro's shirt. "You were at the Final Selection!" he exclaimed, eyebrows raising so high in surprise that they nearly disappeared behind his bangs. "Weren't you? You were, right? I know you!"
"I've never met anyone who acts like you!"
"What?! Do you have memory problems?!"
As weird as this guy was, he sounded genuine, so Tanjiro stopped shaking him back and forth to take a good look at his face. He did look a little familiar now that Tanjiro was paying proper attention, but it still took a good while to recognize the bedraggled blonde that had stood on his left at the end of the test, the one who kept sobbing to himself all throughout the choosing of the ores. Of all the four who had passed the Final Selection, he had seemed the most unsettled, especially compared to the butterfly girl's gentle calm and the larger boy's brazen anger. He had been the only one not to get a crow.
So that was where the sparrow had come from.
The boy sank down to his knees, trembling, and Tanjiro released him before turning to the girl in the kimono. "Sorry about that," he said, forcing a kind smile. "You can go on your way now."
"Thank you!" She bowed and turned to leave.
"W-Wait!" The blonde boy scrambled upright and dragged himself back at the girl's feet, ignoring her startled screaming. "You can't do that! She's going to marry me! She loves me!"
Tanjiro turned his face towards the sky and closed his eyes. Help me.
Luckily for him, the girl took action before he had to, slapping the boy across the face. "I never said that I loved you!" she shrieked, face turning red with rage as she pummeled the boy with her fists. "All I did was check on you when I saw you crying on the side of the road! You creep!"
"What?!" the boy sobbed, flinging his hands up in an attempt to protect his face. Tanjiro rushed forward to drag the girl back—he didn't really know what was going on, but the beatdown was getting a little too violent. "I thought you reached out to me out of love!"
"I have a fiancé—"
"—and you seem fine now, so goodbye!"
The girl spun around and strode off with a flourish, clearly furious. Tanjiro seized the boy again when he tried to crawl after her, tears in his eyes. "Hey, stop—she's not interested, okay? Just leave her alone, will you?" He lifted his head to stare at Tanjiro, drying his eyes with his sleeve. Tanjiro sighed and crouched down to grab him by the shoulders. "She didn't want to marry you. You realize that, right?"
"She...didn't want—" he frowned and ruffled his own hair, seeming distraught. Without warning, he threw himself on Tanjiro, crying again with renewed vigor. "Will you—will you marry me instead?!"
Tanjiro, in the middle pulling the boy to his feet, froze.
"Please, I'm going to die soon—I can't die before I get married, you know!" The blonde sobbed louder and twisted his fingers into the front of Tanjiro's shirt with surprising strength for his size, watery eyes piercing his own. "Will you marry me, then?! If she doesn't want to, then—then—t-then you will, right?"
Tanjiro fucking died. His heart exploded.
He physically felt his face burn, felt himself blush all the way to the tips of his ears and down his neck. The retort he had prepared died on his tongue, coming out as an embarrassingly strangled noise instead. Self-consciousness coursed through his body, the kind of subtle discomfort he used to feel when he visited that nice girl on the corner of the street who bought charcoal every other week. But this was no well-mannered young person with good looks and charisma—this was a sniveling, scrawny, snot-faced teenage boy with yellow clothes and even yellower hair and no sense of dignity. There was no good reason for Tanjiro to be getting flustered like a twelve-year-old talking to their crush for the first time.
(Yet here he was. Tanjiro had thought he'd endured enough suffering getting beaten up by demons left and right for the past couple of weeks, and getting beaten up by Urokodaki for the couple of years before that, but apparently the world had a worse hell in store for him.)
Said snot-faced teenage boy, apparently oblivious to Tanjiro's inner turmoil, mopped at his tears with the back of his hand and slumped down, dragging Tanjiro to the ground with him. "You don't understand, do you," he blubbered, hanging his head. "I'm horribly weak. I didn't even want to become a Demon Slayer, but Gramps forced me to. And—a-and I'm gonna die, I'm going to die on my next assignment—I almost died on my last one and it was supposed to be easy! I can't die before I get married!" When Tanjiro didn't speak, the boy screeched in frustration and threw both hands in the air. "Stop looking at me! Say something!"
"Yeah, I'll marry you," Tanjiro said before he could stop himself.
The blonde stopped babbling and clamped his jaw shut so quickly it was almost comical, staring at him with a baffled expression. Even the birds stopped flapping around their heads to watch. Somewhere down the road, the kimono girl continued to stomp away, completely unaware that Tanjiro was enduring what she had been just a few minutes earlier. No, scratch that; what he was going through was even worse, digging his own grave with his big mouth.
"That..." Tanjiro coughed into his fist and prayed his face wasn't too red. Stupid, stupid Tanjiro, forgetting how to think as soon as he met a pretty boy that really wasn't pretty at all (he tried to convince himself that he was just insane from exhaustion, but it didn't work very well). "...that was a joke."
Desperate for the confused look on the blonde's face to disappear, Tanjiro cleared his throat and stood up, holding out a hand for him to take. "I'm Kamado Tanjiro. How about you?"
A brief moment of quiet, disturbed only by the scratching of the crow's claws against the dirt road, and then—"Agatsuma Zenitsu," he said softly, slipping his hand into Tanjiro's with a broken sniffle. "Sorry about—about—that, I'm just...kind of scared, right now. I don't—" he pulled himself to his feet and wiped his nose with an ugly sob. "I really don't want to die."
He really is pretty. Tanjiro allowed himself approximately two seconds of silent admiration, taking in his shining eyes and vibrant hair and did I mention his eyes? and what is wrong with me and smiled, putting a hand on Zenitsu's shoulder. "You're not going to die. Sorry for being forceful earlier, but...well, let's just talk, okay? Try to calm down."
"You'll protect me, right?! You'll protect me until I can get married?" Zenitsu snatched at Tanjiro's sleeve and held on, his expression so painfully hopeful that Tanjiro couldn't bring himself to say no.
God, Tanjiro was already so incredibly attached to this blonde-haired thing with absolutely zero etiquette, it was stupid. Abhorrent. It was so disgusting, and for some reason there was this disgusting mess of curiosity and abhorrence to this complete train wreck of a person sitting heavy in Tanjiro's gut, and now he just felt disgusting in general. There was snot drying on his shirt, and Zenitsu was rubbing the tears from his face with Tanjiro's sleeve, and it was so hot that he could feel sweat soaking through his uniform. And the warmth that stirred in his chest when Zenitsu looked at him, that was strangely gratifying. Why it was gratifying, he had no idea. They'd known each other for about three minutes.
"Uh," Tanjiro said stupidly. "Uh. Yeah. You—can come with me." Zenitsu stared at him, and Tanjiro rushed to clarify. "On the next assignment! We're headed in the same direction." Stop being dumb, Tanjiro. He gave himself a quick mental shake and grinned wide in a last-ditch attempt to dissolve the awkward tension around them. "Hey, are you hungry?"
Zenitsu nodded, much to Tanjiro's relief. "I don't have any food on me," he muttered. Now that he wasn't crying hysterically, he almost seemed shy. No, he was ashamed. Now Tanjiro was less appalled and more sympathetic. Not that he was excusing Zenitsu's behavior, as asking random girls (and boys, he lamented) to marry you was definitely not normal or socially acceptable, but there was clearly something important bothering him.
Zenitsu was still gazing down at his shoes, scuffing the dirt at their feet. He glanced up and followed as Tanjiro began walking, watching as he reached into his haori and pulled out a rice ball. "Here, have it," Tanjiro said, holding it out.
Zenitsu blinked, hovered his hand over Tanjiro's for a moment before taking it. "Thanks," he said, bringing the food to his mouth to nibble at. After a significant pause, in which he chewed and swallowed, Zenitsu tapped his shoulder and asked, "Aren't you going to eat anything?"
Tanjiro shook his head. "No, that's all I have."
Surprisingly, Zenitsu's face crumpled, as if he was distraught. Barely a second had passed before half of the rice ball was being offered back. "You have half, then," Zenitsu said.
"Really?" Tanjiro beamed, and Zenitsu maybe-smiled back, eyes still red. Adorable. "Thanks!" He took the gift and bit into it immediately.
Truth be told, he hadn't shared anything with a friend in a while. Urokodaki was more of an instructor and mentor, someone untouchable, someone Tanjiro was meant to look up to rather than relate to. He hadn't had a real verbal conversation with Nezuko in literal years, either, not since she'd been turned into a demon. And the last time he had a friend was...when again?
Yeah. Zenitsu was a teenage boy his age and Tanjiro was desperate for human interaction. Sue him.
Tanjiro was cheering up now, though. The road wasn't too lonely anymore, with this walking corn cob next to him. And as weird as it had been, the whole thing with the marriage proposals had done more than enough to stop the boredom that had been plaguing him for the majority of the trip. He was still tired, but, well, he was always tired. He wasn't in that much of a sour mood anymore, and that was nice.
Zenitsu, as if reading his mind, turned to look at Tanjiro out of the corner of his eye. "You're not upset anymore," he said quietly. "Was something bothering you? You seemed kind of unsettled before."
Tanjiro shrugged one shoulder. "I've just been traveling for a while. It gets tiring." He frowned apologetically at Zenitsu. "Sorry for being rude. I wasn't exactly in a good mood."
"No, it's okay. I was—being weird."
"So how about you?" Zenitsu startled and nearly dropped his half of the rice ball. "Something's bugging you too, right? There must be a reason why you would—" Tanjiro grimaced and cursed himself in his head another dozen times. "—propose to people like that. And you said something about dying, right? Even though you're a Demon Slayer?"
Zenitsu's eyes began to well up with tears again. Ah, great, he's crying again. "I got swindled by a girl a while back," he mumbled. "Gramps took over the debt for me, but he trained me half to death in exchange. Thrust a sword into my hand and told me to go to this—this Final Selection." He let out a muffled, pathetic whimper and patted the sword hanging at his hip. "I thought I was gonna bite the dust, but I lived, and now I'm just going through more hell being dragged from place to place, being asked to kill things that scare me to death."
"I mean, it is your job..."
Zenitsu nodded vigorously. "Exactly! And I'm going to die, because I'm technically obligated to at least attempt to fight the demons, which means I can't save myself and run away!" He jabbed a finger in Tanjiro's face. "You've got to protect me, alright? I've still got to get married!"
Tanjiro couldn't help it—the situation was just so absurd, he laughed. "Yeah, I'll protect you," he said. A little softer, he added, "You know, other than the whole obsession with marriage, you're a nice person, Zenitsu. I hope we can be friends."
Zenitsu dropped the rice as soon as Tanjiro spoke and threw himself at his feet again, clutching at his shirt. "Nobody's ever said anything like that to me before!" he blubbered, hiding his face in Tanjiro's sleeve. "Thank you, Tanjiro! I think I'm gonna cry!"
You're already crying, Tanjiro thought to himself. It was a little heartbreaking, though, that nobody had ever complimented this boy. Even back in the mountains with only his siblings and mother, he'd always known unconditional love, always had the company of a close friend with him at almost all times.
Zenitsu smelled lonely. He smelled sad. Tired and mournful and miserable, the smell of someone who hadn't laughed genuinely in years.
"Come on," Tanjiro said gently, bending down so he was face-to-face with Zenitsu. "You're not alone anymore. We'll protect each other, alright? I haven't had a friend in a while, so it'll be nice to have someone to travel with." Zenitsu, in all his dirt-streaked, messy-haired glory, met Tanjiro's eyes and nodded wordlessly.
(Unbeknownst to Tanjiro, Zenitsu had just been thinking to himself about how Tanjiro sounded lonely, too.)
"Are you okay now?"
Zenitsu stared at the sticky grains of rice on his palm, then looked back up at Tanjiro, eyes crinkling at the corners as he smiled. "Yeah. Thanks, Tanjiro."
Woah, he smiled. Just like that, the pretty boy got about ten times prettier, and Tanjiro's suffering multiplied tenfold in tandem. He'd brought this upon himself; he'd helped the kimono girl, given Zenitsu food, offered to travel with him. And now he was going to be traipsing around for who knows how long with a demon on his back and a sniveling yellow shrimp.
It sounded great. Really, genuinely, unironically great. Tanjiro was going to have a friend.
Tanjiro informed Zenitsu "I don't ever plan on marrying you though, sorry," and Zenitsu let out the tiniest chuckle that warmed his heart, and the quietest, most delusional part of Tanjiro's brain berated him for telling a lie for the first time in ages.
Later that day, after they'd defeated the demon in the forest and they were all properly cleaned up (and had a certain boar-headed child/abomination running after them) and Tanjiro was really looking at Zenitsu's face for the first time, his heart continued to explode until he was sure it'd burst out of his chest.
And it didn't stop, not for the next couple of days, or weeks, or months, or years.