Five minutes into Karasuno's first-ever sleepover at Hinata's house, everything had already gone to shit.

Naturally, when Daichi was brainstorming team bonding activities and Hinata had volunteered to host twelve highschool boys over at his house for a weekend, he'd been more than a little hesitant from the get-go. For one, though most of them hadn't actually been over to Hinata's house for more than an hour or so (the exceptions including Kageyama, Yamaguchi, and (surprisingly) Tsukishima), they'd all been inside it enough times to know that it wasn't exactly the right size for a sleepover, especially considering how crazy their particular team could get.

Hinata's house wasn't small by any means, especially for one way up in the mountains. It was more...average, maybe a little below. It wasn't an insult, and as far as Daichi could tell, Hinata's family wasn't struggling financially in any way, but fitting everybody in one place seemed like quite a stretch.

When Daichi had brought these concerns up to Hinata, though, the first-year had just simply waved him off and assured him that it would be the perfect place for a sleepover. His mother was away for the weekend, and contrary to the captain's belief, Hinata had insisted that his house wasn't as small on the inside as it looked on the outside. There was, apparently, a pretty large back living room area that he hadn't been aware of.

Daichi still hadn't been all convinced, however, even after the other three first-years had backed up Hinata's explanation and joined him in insisting that Hinata's house would be the perfect place to host such an event. Everyone else had seemed pretty keen on the idea too, most of all Tanaka and Nishinoya, who'd been absolutely ecstatic at the prospect of adequately seeing the inside of their favorite underclassman's house for the first time.

In all, the debate was over pretty quickly. One harsh glare from Suga and sparkly puppy-dog eyes from Hinata was all it took to push the captain over the edge and reluctantly agree, much to the delight of everyone else, including Tsukishima for some reason. He seemed oddly adamant about going over to Hinata's house, and when Daichi had asked about it as the two were packing up, the blond had simply shrugged and said:

"You'll see. Just make sure to bring a pair of sunglasses."

At the time, Daichi had had no idea what Tsukishima meant, but he suspected it had to do with the small little girl that immediately leaped into Hinata's arms as he entered the house with his teammate behind him because holy shit, there were two of them.

"Shouyou!" The little ball of orange fluff squealed, and everyone's mouths dropped.

As if that wasn't bad enough, Hinata's face exploded into the softest, most affectionate smile any of them had ever seen and holy shit no wonder Tsukishima was so keen on going to Hinata's if this was going to happen all night. "Hi, Natsu!" He pressed an exaggerated kiss to her cheek and ruffled her hair. "Didja have a good day?"

"Yeah!" Natsu wrapped her legs around Hinata's waist and reciprocated with a kiss of her own, a smile that could almost rival Hinata's adorning her features. "It was awesome! The teacher said we were so good this week that she would let us have an extra-long recess next Monday!"

"I'm sure you're excited about that, huh." Hinata gave his sister one last smile before gesturing to his teammates meaningfully over his shoulder, to which everyone had to literally struggle to regain what little composure they had left to move. The effect Hinata had on them alone was bad enough, but now they had to be in the constant presence of two sunshine children for the duration of the weekend? What the hell kind of genes did they even have? "Natsu, I'd like you to meet some people."

"Oh?" Natsu twisted her entire body around to stare at the open-mouthed highschoolers, seemingly realizing her brother had company for the first time that night. She scanned the crowd quietly, her smile falling from her face and forming an adorable pout with unconscious puppy-dog eyes that weren't quite as glittery as Hinata's but could do the trick nonetheless. "Are these your volleyball teammates?"

"Mmhm." Hinata gently unlatched Natsu's arms from around his neck, his sister getting the message and quickly climbing the (short) distance down her brother. "I bet you remember some of them."

"Tobio?!" Natsu's face brightened instantly, her smile falling back into place as easily as anything. "Is he here?"

Hinata wrinkled his nose. "Duh, he's on my volleyball team." He mimicked his sister's earlier pout, and Karasuno had to collectively suck in a breath because there was no way they were going to last the entire weekend without cracking and what the hell was going on. The Hinata siblings, bless their souls, didn't notice a thing. "He's probably hiding in the back somewhere or something." He flicked Natsu on the forehead. "He gets nervous around you, you know."

"I do not." Kageyama's voice filtered from somewhere near the middle of the group, sounding a lot less grumpy and way more squeaky than usual. "She's just so freaking adorable, it's like-"

"Ewww, Bakayama!" Hinata's words were nearly drowned out by Natsu's flustered stammering. "Don't say that you weirdo, she's like the younger girl version of me!"

"That's the freaking point, dumbass," Kageyama muttered, audible only to himself and Yamaguchi standing behind him because the Hinata siblings were so undeniably cute he wasn't sure if he wanted to punch them in the face or squish their cheeks. He wasn't as affected as the others were by Hinata most of the time, mainly because they spent every waking moment together and life would be impossible if Kageyama had to pick his jaw off the floor every time the middle blocker so much as smiled, but standing in a room in the presence of two freckled, fluffy, smiling gingers was like staring into the sun, but, like, increased by ten with kittens eating cotton candy thrown into the mix.

Jesus Christ, what was their mother feeding those kids? It was probably the tears of puppies with sparkles and rainbows mixed in or something. Either that or their genetics were out of this world.

"So, this is Natsu." Nishinoya murmured, eyes blown wide and volume significantly lower than usual. "Huh."

Yeah. Huh.

"You know me?" Now it was Natsu's turn to look confused, coming out from where she'd hidden her face in her hands to look around the room curiously. "How? I don't know any of you."

"Ah." Nishinoya cleared his throat weakly and raised his hand. "Hinata talks about you sometimes. And, uh-" since when was forming words so freaking hard. Goddamit, he could've sworn he was getting better at this. "Uh, sometimes Hinata has to leave early to...y'know. Take care of you and stuff."

"Oh. Okay." Natsu nodded in understanding, adorably nibbling on her fingernail as she took in the libero's appearance. "You're short."

Nishinoya couldn't even muster up the energy to protest. Jesus, it was like meeting Hinata all over again, except this time, the kid was fun-sized.

Hinata giggled behind his hand, and for the love of God, could the Hinata siblings please give them just a moment to breathe. Being in the same room with Hinata all day was already tasking in and of itself, and while seeing his smile added about ten years onto at least one person's life daily, it was just so hard to stay composed as the poster child for purity flounced around making everyone's hearts feel like they were going to explode and/or melt.

And now they were standing in front of two rays of sunshine, both of which seemed to be working double time because if they didn't stop looking so goddamn precious in the next five seconds, at least one person on the team was going to scoop at least one, if not both, of them into the biggest bear hug they'd ever received.

Luckily for Karasuno's sanity (as well as pride, composure, reputation, etc. etc.) Hinata averted his gaze from his friends to look fondly down at his baby sister. It wasn't much better, seeing as it only amplified the urge to coo at the pair, but at least they didn't feel like they were going to melt as severely.

"Would you like me to introduce you to all of them? I'm sure you'd like them very much."

Natsu nodded enthusiastically, returning her big brother's gaze with just as much adoration.

"Okay." Hinata gestured for his team to step forward. They obeyed, albeit hesitantly. After all, too much exposure to the sun(s), and you could burn right up. "You already know Kageyama, Yamaguchi, and Tsukishima, right?"

Natsu nodded again, no one missing how her cheeks heated up at the mention of the blond blocker's name, which only reddened when said blocker cast an uncharacteristically gentle smile her way. Hinata was well aware of his sister's strange puppy crush on his teammate, something he found both adorable and super freaking weird. He decided not to say anything, though. Natsu could pack a mean kick if she wanted to.

Hinata adjusted his finger so it was now pointing at the captain and vice-captain. "Those two there are Suga and Daichi, and the big one behind them is Asahi." Natsu lifted her gaze to meet Suga's, noticeably shyer than before. "They're third years. They're all really really nice even though they look a little intimidating." He nudged her forward. "Say hi."

"Hi." Natsu waved meekly up at the three. Asahi waved back just as gently. Suga put his hand over his heart and "awwwwed" softly. Daichi's gaze simply flickered from one ginger to the next, somehow managing to look bewildered and so so so soft at the same time. "It's nice to meet you."

"It's nice to meet you too, sweetie." Suga slowly got on one knee, looking at the little girl at eye-level. Not for the first time, Asahi envied how easy his friend was able to communicate with kids. He should seriously think about becoming a kindergarten teacher or something. "We're very fond of your brother."

"Mmm." Something changed in Natsu's expression, but it was gone as quickly as it had appeared. "That's cool! I am too."

Hinata laughed and ushered Natsu to the second group of people. "Now, these three here are Ennoshita, Nishinoya, and Tanaka. They're all second-years on my team."

"Oh!" The look in Natsu's eyes changed from bashfulness to recognition. She turned to Nishinoya. "You're Nishinoya, aren't you! My brother always talks about how cool you are. Once, he came home from a game and told me that you saved a ball with your leg!" She bounced up and down on her heels, suddenly energized. "He thinks you're so awesome!"

"I-" If Nishinoya were a less prideful upperclassman (which he wasn't, but that wasn't the point), he would've burst into tears on the spot. Shouyou? His Shouyou? His underclassman talked about how cool he was, not just to flatter him in public but with his sister in private having no way of knowing the libero would ever hear the things he said? God, the self-control it took not to cheer out loud and give Tanaka the smuggest smirk ever. "Really?"

"Yeah!" Hinata was grinning wildly, utterly oblivious to the fact that his sister's confession had just made his upperclassman's entire month. "Don't I tell you all the time? I think you're amazing!"

If Nishinoya felt tears well up in his eyes, that was no one's business but his.

"Shouyou-"

The libero was cut off by Tanaka jabbing a thumb in his chest. "What about me? Has he said anything about me?" His voice was unnaturally fast. Frantic, even.

Natsu innocently blinked up at him. "You're Tanaka?"

"Yeah?"

"Oh." Natsu nodded resolutely, serious as ever. "He always says you're pretty fantastic too." If she noticed how Tanaka's chest puffed out in pride, she didn't acknowledge it. "Sometimes, he says he thinks of you as an older brother."

Tanaka choked, stammered for a moment, then stared at Hinata like the ginger had just handed him a million dollars.

In Tanaka's world, he might as well have.

Hinata just nodded and laughed, furthering confirming Natsu's statement and inflating Tanaka's ego tenfold.

Ennoshita just grinned and waved over the shoulders of the other two blubbering second-years, thankfully not wanting to delay introductions any longer. As cute as Hinata's sister was, she was nothing to Hinata's little kitten sneeze he'd heard a few months back. After that little display (and after playing it on repeat in his mind for like one hundred times while arguing with Kinoshita and Narita about how exactly it'd happened), he was pretty sure he was immune to cute things for life. Plus, they had the whole weekend together. He could get to know her some other time.

"Hm." Hinata scanned the group for a moment. "I think that's everyone. You already know the first-years, and the other second years are coming a little later after they finish test prep."

"Oh?" Natsu turned to her brother, ever the curious sibling. "What are the other second years' names?"

"Kinoshita and Narita," Hinata replied smoothly. "Don't worry. They're super-duper nice. You'll meet them in like an hour or so."

"Okay!" Natsu smiled. "That sounds good."

"Mmhm." Hinata absentmindedly glanced at the clock above their stove. "Listen, I have to check in with my mom right about know and let her know me and Natsu aren't dead and stuff." He ruffled his sister's hair and bopped her on the nose. Yamaguchi, unable to contain himself, let out a little "awww." "Can you show my friends the back living room so they can set up their stuff for tonight?"

"Sure thing!" Natsu shot him a double thumbs up. Hinata beamed.

"Good to hear." He winked at his teammates, ruffled Natsu's hair one more time, and disappeared into the house and out of their sight.

There was a moment of silence as everyone watched him leave, and in the split second the boys looked away from Hinata's disappearing form and back to his sister, her face had changed completely.

Natsu's expression turned stormy, her commanding demeanor making her seem much older than just a little girl.

"Listen." Her voice was still as high and girly as it had been before, but there was something, some undertone or something too it that made it sound much more intimidating. The players froze, not having been prepared for whatever this was at all. "My brother is the best person I know. He's kind, he's playful, and he's the greatest big brother ever." She frowned, scanning the group of boys with eyes much more calculated than they should be. "But he's a little too trusting. So, I've taken it upon myself to be his protector!"

She jammed her thumb proudly at her chest despite the contradiction between her cutesy actions and cold words.

"He loves you all a lot." She continued. "But no matter how great he always says you guys are or how fondly you look at him, I don't know if you deserve my big brother's friendship." The pout was back again at full force. "Show me how much he actually means to you, and maybe I'll consider letting you off the hook."

There was a perilous moment of silence. No one dared to breathe.

And just like that, after one last glare, Natsu's silly smile and little kitten eyes were back. "Except Kageyama, Yamaguchi, and Tsukishima." She beamed. "I already know you guys care about him, so I won't have to be judging you this weekend."

Kageyama choked, Yamaguchi grinned, and Tsukishima looked oddly flustered (and a little defensive, but there was no way he was going to say anything in fear of facing Hinata Natsu's wrath, which was apparently much more deadly than anticipated.)

The rest of Karasuno, however, could only watch in a mixture of mute wonder and horror at the return of Natsu's almost toddler-like persona.

Ah, so that was the distinct difference between the Hinata siblings, the reason Hinata's actions and nativity seemed so much more pure and genuine.

Natsu knew how to control whatever cute genes she had, while Hinata didn't even know he had them and just let them spill out all over the place while simultaneously giving people heart attacks whenever he so much as smiled at them.

To sum things up, Hinata was the epitome of an angel.

Natsu was a devil disguised as one.

But of course, if winning over a cunning little sister was what it took to enjoy a weekend with Hinata, then that was exactly what they'd do.