The rain never stopped.
It hammered against the rooftop in a steady, almost hypnotic rhythm. Brian had long since stopped noticing it as discomfort. It was no longer an annoyance—it was a constant presence. The world breathing, endlessly.
Standing at the edge of the rooftop, he held his fishing line over the dark water below. What had once been a street was now a shifting, murky surface filled with debris and faint reflections.
He waited.
Then the line trembled.
And suddenly tightened.
Brian froze instantly.
The pull was wrong. Too erratic. Too violent. It wasn't the usual struggle of a fish—it felt… chaotic.
He began reeling it in slowly, controlling every movement, his eyes locked onto the surface below.
Then he saw it.
Not a shape.
Not a body.
A light.
A faint, irregular glow pulsing beneath the water, like a weak heartbeat.
Brian narrowed his eyes.
"…phosphorescence?"
The glow grew stronger as it approached, fragmenting into multiple points, uneven and unstable.
Then the surface broke.
The fish burst out of the water, thrashing violently at the end of the line.
And this time, Brian saw everything.
Its scales were glowing, scattered in irregular patches, emitting a pale light that pulsed beneath the rain. It wasn't uniform. It wasn't natural. It felt unstable—almost sick.
His gaze moved instantly across the rest of its body.
Sharp spines ran along its back, overdeveloped and rigid, far beyond what should exist on a fish of this size.
Its jaw snapped open.
And there—
Teeth.
Thin. Numerous. Sharp.
Not the kind meant for grazing or passive feeding.
These were made to tear.
Brian didn't move for a second.
Then a single word formed in his mind.
"Mutation."
Without hesitation, he grabbed a hook and dropped the fish into a container filled with floodwater.
The fish didn't calm down.
If anything, it became more active.
It circled violently, slamming against the sides, its glow pulsing faster—as if reacting to stress.
Brian crouched down, completely focused.
Already analyzing.
The body shape…
Slender. Elongated.
Fin placement… proportions…
Something about it felt familiar.
His eyes locked onto the dorsal line.
The spines were abnormal—
But the structure beneath them…
Recognizable.
"…No way."
His mind was already searching.
A small freshwater fish. Gregarious. Invasive.
Images flashed through his memory.
Then a name surfaced.
"Pseudorasbora parva…"
He stayed still for a moment.
Then stood up abruptly.
Inside.
He moved quickly into his apartment, heading straight for his bookshelf. His fingers ran along the spines of multiple volumes before pulling out a manual on invasive freshwater species in Asia.
He opened it immediately.
Pages flipped quickly.
Then stopped.
Same body structure. Same proportions.
But what he had captured…
Was something else entirely.
Brian returned to the rooftop and placed the book beside the container.
His eyes moved back and forth.
Image.
Specimen.
Comparison.
Analysis.
Confirmation.
"That's you…"
But changed.
Transformed.
He didn't kill it.
Not yet.
Brian filled several smaller containers with floodwater and added a few other fish he had caught earlier.
Then he introduced the mutated specimen.
The reaction was immediate.
It attacked.
Fast. Precise.
It bit into a smaller fish, forcing it away. The others clustered together instinctively—but didn't flee entirely.
Brian leaned closer, watching carefully.
"Gregarious… but aggressive…"
He grabbed his notebook and began writing.
"Specimen identified as probable derivative of Pseudorasbora parva. Visible mutations: overdeveloped dorsal spines, carnivorous dentition, irregular phosphorescent scales."
He glanced up briefly.
The fish was still circling, clearly dominating the space.
"Behavior: social but hierarchical. High aggression. Rapid dominance established."
He adjusted the light slightly.
The glow changed.
Stronger in shadow.
"…Light response…"
He wrote again.
"Phosphorescence appears adaptive. Intensity varies depending on environment."
He observed a while longer.
Then closed the notebook slowly.
Now came the next step.
Dissection.
With careful precision, he immobilized the fish on a metal surface.
The blade met resistance as it cut through the skin.
Denser than expected.
Inside… things were wrong.
Organs enlarged. Others shifted. Some structures… unfamiliar.
Brian didn't speak.
He wrote.
Sketched.
Compared.
The world outside no longer existed.
There was only this.
Understanding.
When he finally looked up, night had fallen.
The children were watching from a distance, silent.
Brian remained still for a moment.
Then wrote one final line.
"Day 6. Mutation confirmed. Accelerated adaptation observed. Potential ecosystem impact high. Hypothesis: phenomenon not limited to aquatic species."
He closed the notebook slowly.
Outside, the rain continued to fall.
But now, Brian understood something.
The world wasn't just drowning.
It was changing.
[Brian's Field Notes – Day 6]
(Fish illustration)