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Chapter 1: The End of Summer

Day 0

The cicadas were noisy, and their discordant cries could be heard echoing from the nearby trees.

Amidst the sweltering heat, the school bell rang, stirring the dead-fish eyed loner from his daze. Spring had officially ended, and members of the go-home club lost no time in celebrating the start of summer break before exam preparations would begin. Alas, for him, the day was far from over, and as the pink-haired airhead came by with her bag packed and ready, he merely grunted in response before taking a sip of the heavenly brew that he had bought earlier.

Hell, even my MAXX coffee is warm in this weather.

"Hikki, the classroom is nearly empty," she exclaimed, "you could have your fill later, I'm sure Yukinon would've made us some tea."

Thanks, Yuigahama, but only the ice queen of Chiba could stomach a warm drink in this climate.

"Besides, you wouldn't want to keep her waiting, would you? And your little sister too."

They're fully capable of entertaining themselves, but yeah, I guess you've got a point.

With that, he finally stood up, refreshed by the caffeine in his system. It would be the last session of the term, and while he was neither a student who loved classes nor a person who needed the company of others, he could not help but feel that the holidays would be that much more boring without the afternoons that he had come to embrace. Of course, they could always take a break from studying and meet up sometime - it was not as if the world had ended - but it would somehow be different, without the clubroom in the backdrop.

Can't believe it was just last year that the chain-smoking, gut-punching teacher had to drag me here.

Hiratsuka-sensei, hope you have better luck and less trouble at the other place.

"Yo," he was greeted by a familiar scene, not that he would wish for anything else. Book in hand, the raven-haired figure sat beside the window, his mischievous junior and kawaii imouto seated opposite her, engaged in friendly banter.

"Good evening, Hikigaya-kun," she smirked, an innocent smile had he not known better.

"Onii-chan, osoi!" his little sister was ever so straightforward, "That cost you a hundred points!"

Please, anything but that, Komachi!

"I was just about to leave," the flaxen-haired vixen huffed in mock annoyance, "Did you decide to play hooky and change your mind at the last minute to come see me instead? I appreciate the gesture but sorry, I can't accept your confession."

"Isshiki-san, do you not understand what a 'couple' means?"

"Yeah, it means a few," the President of the Student Council who was recently re-elected stuck her tongue out cheekily as the others turned red in a mix of frustration and embarrassment.

"Anyways," she continued, deftly changing the subject before the joke could turn sour, "it's shaping up to be a hot July and I'm thinking of catching the swimsuit sale in town today. You girls are welcome to join, last year's attire is getting a little tight on me."

"Eh, you too?" the airhead was quick to agree, "The fabric around there just isn't elastic enough–"

"I see all that snacking must've taken its toll," the ice queen retorted, not wanting to hear the rest.

"I think I'll pass," the younger Hikigaya spluttered, similarly depressed.

"Whatever, I'll go myself then. Lemme know if anybody wants to hit the beach next week. Forecasts say it'll be all bright and sunny. Text me later, senpais!"

Grinning, she strode out the door, and silence re-established itself, a calm quiet that he did not care to disrupt. Taking a deep breath, he made himself comfortable beside his raven-haired partner, who appeared to bury herself in her novel, stealing a few shy glances at him from behind the pages while he pretended not to notice.

Something on your mind, Yukino? Else I'll just enjoy the tranquillity and let the hours tick by.

"Say, what're your plans for summer, Komachi-chan?" the airhead was the first to break the silence.

"Besides sleeping, eating, lazing around and doing homework?" his little sister glared in his general direction, "Probably hanging out with my friends so someone can bring his girlfriend on proper dates."

"Hikigaya-kun, where'd you like to go?" she questioned, taking keen interest in the conversation, "We should arrange a few of those."

Is that what you've been wanting to discuss? Well, I'd say the sea would be–

Hold on, that idea was sneakily planted in my head just now, wasn't it?

"Any suggestions?" he pondered aloud, "We've been to the mall, the aquarium, Saizeriya, Destiny Land, the school festival, the clubroom–"

"Be a little more creative, gomi-chan!" his little sister chided before he could ramble on.

"Anywhere would do, really," she assured with a blush, "You could come study at my place if you'd like."

"Gah, you guys just reminded me that I have remedial lessons to attend!" the airhead groaned. "Why does math have to be so difficult? Even baking nice cookies is easier than messing with calculus."

"Because you'll still need to pass to get into college," he muttered, reminding himself as much, "and get a job like our conformist society demands and work all day for at least the next three decades until your kids grow up and are able to support themselves to raise spawn of their own. Such is the fate of the individual and the propagation of the species–"

Bzzt.

Huh?

He was abruptly cut off as the lights went out and the air-conditioner stopped whirring, plunging the atmosphere in the room into a literal standstill. Even Yukino's favourite kettle had stopped bubbling, and the sound of the cicadas seemed to grow in the absence of noise.

In the deafening silence, he left his sentence hanging, having lost his train of thought. In a country where precision was the norm and things ran like clockwork, unannounced power outages were rare, and he could not help but indulge in the uniqueness of the situation, a serenity devoid of movement and activity save for the steadily rising temperature and the sweat forming on his brow.

It was as if the entire metropolis of thirty million had gone quiet in an instant.

Wait, what?

Glancing out the window, he nearly fell from his chair. Dozens of sedans had come to a halt in the middle of the street, clogging up lines of other equally stunned motorists. Curious onlookers rushed to push the stalled automobiles aside while desperate drivers scrambled to restart their engines, but the sheer number of jammed vehicles was simply impossible to believe, much less comprehend if it was not staring him in the face.

What on earth is going on? Am I hallucinating? Cars run on gas and batteries, not the mains.

What's next, would I see planes falling from the sky?

"My phone's dead," the airhead grumbled as an unmistakable sense of fear and dread washed over him, adding fuel to a fire that was festering in a dark corner of his mind.

"You can have mine, Yui-senpai," his little sister offered, only to retract her outstretched hand a second later. "Eh? It's out of order?"

No, it can't be. It's burning in here. The heat must be getting to me.

Why else would I be dreaming of something as ridiculous as an EMP?

Iroha had just arrived at the retail centre in the suburbs of Tokyo when she sneezed, wiping her nose with her handkerchief.

Heh, bless me, did someone just mention my name?

Snickering, she paused for a moment to take in the scenery. Flanked by affluent neighbourhoods like the one she lived in, the shopping strip was situated on a hill overlooking the capital, offering a panoramic view of the city below. The cafes were packed, with rich kids imbibing themselves with overpriced juices between lively afterschool chatter. The beach was the other way, beyond the skyline, and she told herself once again that the sea was where she truly wanted to be.

If only he was here with me, she mused, reminiscing a time not too long ago when she could go on practice dates with him - not that the presence of a goalkeeper ever stopped the manager of the soccer club from trying. Then again, even if the others were to insist on coming along, she would probably be as appreciative and happy, not that she had anyone else to turn to when her parents were stuck working abroad till the end of the year. Tightened border restrictions amidst the recent flareup between the East and the West had cast a shadow over her plan to spend her holidays with family, and the prospect of being cooped up like a shut-in for weeks, staring at the ceiling and the walls and the doors at home was already sending shivers down her spine.

Senpai…she sighed, realising that she had been standing idly under the sun. Somehow, the desolate silence was getting on her nerves, despite more patrons shuffling onto the sidewalks and the warm outdoors. Perhaps it was not too late to call the rest, she thought aloud, digging into her skirt pocket for her phone, only to find that it was wretchedly out of signal range.

Just when I needed it! What's up with this stupid device? This is part of Tokyo, not some far-out village like Hinami-whatnot.

And what's up with the crowd here? Are the restaurants always this dark? Urgh, I'll just have to fix the darned thing and meet up with them at the beach tomorrow, or next week, or next month, or whenever they're free.

Having lost the mood, she turned to walk down the slope.

Seconds later, the world whited out as she was blinded from behind.

"Yukino!" he remembered screaming as he pulled her to the floor, just a moment before flashes brighter than a thousand suns erupted in the distance, the combined energy of megatons of TNT completely destroying, obliterating, annihilating everything in its path for miles on end. Indomitable shockwaves of plasma and molten debris from multiple detonations swept and reverberated across the land, superheated hurricanes uprooting structures from their very foundations and turning office buildings and apartment blocks into powdered bricks and rubble, their occupants simply evaporating from existence while the unfortunate ones struggled to extinguish the fires on their skin.

The ground shook and the windows exploded as she flinched under him in speechless terror, her teapot and cups shattering into shards of clay and porcelain. Loose pieces of paper fluttered in the air which stank of death and charred matter, before flying out with the reverse stream of negative pressure caused by sublimated vacuum in the blackened epicentres. Angry mushroom clouds towered high above the conflagration of indiscernible corpses and mangled wreckages, a nightmare only seen in documentaries and remembered by those who had lived through the horrors of a dark time, made orders of magnitude worse by the advancements in technology in the decades since the last disaster.

For a long while, the four of them lay still and motionless, even as the rumbling storm dissipated into an eerie silence, the ceaseless cries of the cicadas muted by the crackle of flames lighting up the trees.

"Hikigaya-kun," whimpered the pale, shivering figure that was a sharp contrast from the ice queen that he knew, as if he had been momentarily warped to another world by the nukes.

Yukino, thank goodness you're unhurt, was all he could muster as he pried away the quivering hands that clung to his shirt. Steeling himself, he pushed her aside to check on his little sister, relieved to find that she was mostly unscathed, save for the lacerations on her arms and legs from the broken glass.

"Yui-senpai," she wept, staring tearily at the airhead who did not seem to respond.

Hoping for the best yet preparing for the worst, he reached over to feel her pulse, his own heartbeat racing in his chest, cold sweat trickling down his back. In the unnerving quiet, the others looked away, unable to breathe or watch in the suspense, until he stammered that she was merely unconscious, having been knocked out by the fall.

At least everyone in the room was alive, for now.

As for those outside–

Gripped by untold agony, Iroha tumbled on the pavement, barely able to hear the frantic shrieks of the stampeding masses through her ringing ears. Shoving her from behind, the blast had emptied her lungs and sent her rolling, tearing merciless wounds all over her cheeks as she clutched her head in misery. Nauseated and disoriented, she threw up on the asphalt, which did little to alleviate the stinging sensation on her reddened legs as she choked and heaved in absolute despair and helplessness.

What's going on? Why is this happening to me? Senpai, where are you–

Gritting her teeth, she slapped herself to stop the spiral of wallowing self-pity. She was not dumb, the gargantuan column of thick smoke darker than the night billowing from the enormous crater in the middle of the city told her enough about what she needed to know about the situation. World War 3 had struck in broad daylight, and she was alone in a place where she did not belong, more than a dozen kilometres from the friends and acquaintances who could be in danger and in need of assistance - with no way to contact them, no line that she could use to report her status, nor the means of transportation to return to Sobu and see for herself that they were fine.

Clenching her fists and biting down hard on her lips, she gathered her resolve and forced herself to stand up. It was a stupid, hare-brained, impossible idea, one that she almost expected to regret later, but she was a strong and stubborn girl, and there was truly nothing for her here but chaos and pain.

Ignoring the wail of the air-raid sirens and the urge to break down and hug her throbbing knees, she staggered and hobbled down the road to Chiba.

A/N: I'm back this week with a brief chapter, taking a break from the ongoing Konosuba x SAO crossover Blessings on This Floating Castle. Feel free to check out my earlier completed work Reality Offline (SAO x Oregairu post-apocalyptic AU) which is thematically similar but more action/adventure-oriented compared to this piece which will be slower-paced and more grounded (and naturally feature more characters such as best girls Kawasaki Saki and Miura Yumiko - both of whom I like and the fandom here really love).

The cicadas and Hinami(zawa) are references to Higurashi: When They Cry.

P/S: I have a number of leaves in real life to clear this month, and depending on the response, I'd be updating this or the Konosuba crossover.

As always, favs/follows/reviews highly appreciated!