This is one of the contributions to a fan-fiction contest we had some time ago. It used to be a part of the Aftermath site, and will soon be part of the StrategyCore site. In the meantime I'm posting it here.

Written by Skonar.

The public telephone handset hung loosely from its
cable. It hummed helplessly. No one seemed to care
anymore.
A young man came around the corner, bandana tied
around his head, rifle held loosely in his left hand
while he checked each phone's card slot or coin return
cup. He paused to stare up at the murky sun, tear the
bandana from his head and wipe away the sweat.
"I think, I think it's gonna happen again. It's
darker than it was yesterday. It's hotter, too."
Another slightly older man rounded the corner,
keeping the muzzle of his own rifle, black and sleek,
low. He watched the corners, eyes sweeping over
dessicated and dead trees, abandoned cars, the still
flickers of sunlight on broken building windows.
"Hush up" The older man hissed, watching the streets
carefully.
The young man frowned, taking hold of his rifle's
barrel, setting the stock against the ground, leaning
on it. "There's nothing here, old man. Stop trying to
scare me, let's just try and find some food before we
have to go back to the others."
The older man shook his head, lowering his rifle
slightly. "You quit worrying about that, and you just
think about them. The enemy."
The young man shook his head, his face crumpling with
misery. He continued along the row of phones, checking
each one. "I don't wanna find any of those things, old
man. I just wanna eat tonight."
"Like I said. Quit your whining. We haven't run out
of food yet, and we're sentries, not foragers."
A gust of wind whispered down the street. In the
building across the street, broken shards of glass
were disturbed in their windowpanes. Fragile slivers
tumbled free, scattering light as they fell. Old wood
crunched, the sound filtering through the windows and
into the streets below.
Both men looked up. The older began across the
street, sweeping his eyes across the urban landscape
intently.
"It's probably nothing. The wind just disturbed
something. ... Damnit! Don't leave me here"

The office block was a tomb. Bulletin boards posted
up with department memos and ads told the story as
surely as any grave marker or epitaph. Instant
photographs pinned up of flashing lights in the sky.
News clippings, photographs of the dimming sky. Images
of the alien spores as they grew and multiplied in the
clouds, drifted to earth like a steadily expanding
biological rain. Beyond that it was as empty as the
choking nothingness the world had become.
Life stirred, and boarded-over plate glass windows
lost one board, dull orange sunlight stabbing through,
illuminating motes of dust. More boards were pulled
away, until the balcony door could be opened.
The older man tucked a crowbar back into his rucksack
and slung it over his shoulders. Picked up his rifle,
and advanced through.
The young man pulled himself up the fire escape after
the older man, rifle hanging from his back. "We
shouldn't be here," he whispered.
The older man stalked down the rows of desks,
ignoring the dead computer terminals, the abandoned
litter, the shaggy rags slumped in a chair that had
once been a body.
The young man stepped through after the older man,
touching the dusty keyboards as he went past. "I was
studying to do computer engineering," he whispered.
His gaze moved on. His breath caught in his throat as
he saw what had passed for a human being once.
The older man continued on, pulled open the corridor
doorway. He stepped on into the gloom even as the
young man ran after him. The older man counted
doorways. He held his rifle steady with his right
hand, approached the second to last doorway and
reached for its doorknob with his left.
The young man pulled in a gasping breath, afraid in
the darkness. "... Old man?"
The older man had his hand on the doorknob. He turned
his head, and hissed, "Quiet, you fool! Something will
hear yo-"
His words were cut off by a heavy coughing bark,
flakes of bone and flesh chipping through the door's
wood in hollow crunches, a sickening slap of impacts
on flesh. The shuddering inhalation of lungs filling
with blood.
The young man stared helplessly at the older man.
"Hel... help..."
The young man took two steps closer, spasming hand of
the old man pulled at the younger man, twisted in the
dangling strap of the young man's rifle.
Leathery flesh brushed against the door, scraping
against the wood, the weight cracking it.
The older man gasped, his breaths bubbling through
his ribs. "Puh... Please... Hel... Help..."
The young man pulled away frantically, out of the
rifle's strap to get away. He ran down the corridor.
The door gave way, and a mangle of human limbs pulled
through.
The young man pulled open another door at random,
glancing back as the older man tried to scream through
the blood.
The thing pulled through that broken doorway, a
twisted mass of flesh and limbs, slack-jawed faces
staring from its bulk in silent screams. An orifice
quivered, and the flesh shook as it coughed again,
bone and oozing flesh tearing through the remnants of
the old man.
The young man pulled the doorway shut behind him. He
could hear that thing, rustling as it moved.
He hauled breath into his shaking body, and shoved a
desk in front of the door. He backed away from it as
the rustling neared, jerking in fright as his back hit
the wall.
He looked up at the passive features of Christ on the
cross, immortalized in a glossy wall poster. The young
man fell to his knees, clasping his hands in front of
him. Tears dripped down his nose, he leaned his
forehead against the wall in resignation.
"Our Lord, who art in heaven..."
The desk shook and dragged over the tiling as the
doorway pushed in.
"Ha... Hallowed be thy name..."
The door broke inwards.
He looked up at the poster, and sobbed.
"Please help me... Someone..."