After the Little Heartbreaker Fish Comes Ashore in Detective Conan, Breeding Season Begins

[First-draft blurb. The worldbuilding will be fleshed out further.]

[Slight harem appeal, Ginzo pairing, everyone else is platonic]

Also known as: The Trashy Little Fish with a Seven-Second Memory Gets Even Trashier

Also known as: Ginzo and the Aladdin Sea God, Ginzo, Your Fish Got Away, Ginzo, You've Been Played, Ginzo: I'm Fish Food / I'm a Fish Farmer

#

At first, it was just a rumor. A mermaid had been caught off Mermaid Island.

Ginzo went there on the Organization's orders to find the secret to longevity. He came back empty-handed, but then saw someone in the back seat of his Porsche: a person with shoulder-length blue hair, golden eyes, and a beautiful fish tail, who called himself Cang Zhuguang and transformed his tail into legs right in front of him.

Cang Zhuguang: I'm the Sea God of Mermaid Island. There's a goldfish, a silverfish, and a real fish here. Pick one.

Ginzo: ?

Fish: I'm easy to take care of. I just need a fish tank, though a bathtub will do.

Ginzo: ...

Everyone has threads on them. Gods don't.

Cang Zhuguang is a juvenile Sea God, and the only one who can see these threads. Red threads represent the depth of one's bonds, while black threads represent greed, murder, fear, and terror. If a black thread isn't undone, a person's soul will be trapped after death, eventually giving rise to resentment.

Only an evolved Sea God can undo black threads and guide souls onward. But Cang Zhuguang's cultivation had stalled for nearly a hundred years. He'd failed to take human form several times and had nearly been caught and hauled away.

That was until the silver-haired man came to the island. He didn't have a single thread on him.

Cang Zhuguang had never seen anyone so untethered, with no attachments and no memories of the dead. The dense aura of the dead leaking from him instantly cut a century off Cang Zhuguang's cultivation, letting him grow a pair of legs.

For a hundred-year-old mermaid who hadn't come of age yet,

he desperately needed this deathly aura to help him get through his growth period.

Fish: Human, you smell so good...

The man left soon after, suddenly getting out to smoke, with the car door wide open.

So Cang Zhuguang set his sights on the Porsche parked by the shore.

Cang Zhuguang flicked his tail. It vanished, becoming a pair of legs he could stand on.

He prepared one goldfish and one silverfish, intending to ask the man if he wanted an actual little fish. Cang Zhuguang was a hundred years old and still underage, so he could be raised.

As a bonus, he didn't eat much. The man just had to let him take a little sip now and then.

*

Ginzo picked up a fish, a bold little thing who pestered him to go on missions every day.

The fish had only just become human and wanted nothing but to evolve. He was all appetite and had no basic life skills, so Ginzo ended up raising a fish while playing both father and mother.

Every day, when Ginzo came back from a mission

The starving fish: You smell so good. Let me have one sip, just one, then another.

Ginzo: ...

One day, after feeding on him, Cang Zhuguang realized something felt different from usual. His appetite seemed to have changed. Ginzo's gaze was exactly like the way he looked at food, and he was so startled that he popped back into a real little fish.

The fish tested the waters in his true form: Can't turn back? Kisses from a little fish mouth work too.

Ginzo: ...

A year later, Cang Zhuguang's human form had fully stabilized, and he no longer needed to eat. He dusted himself off and left a letter before walking away.

[The dead have increased lately. I have to return to the sea and evolve before investigating the cause on land., Fish]

There had to be a source behind the sudden increase in the dead.

After evolving, Cang Zhuguang could summon the dead, hear their final words, and see images of their lives.

He'd also lost his memory. It felt like he'd forgotten someone, but he couldn't remember who. The important thing was to get on with his business.

So, following the scent, he arrived at the Mouri Detective Agency in Beika Town.

Gradually, the Beika Town detective duo became famous. One was good at deduction, the other at spotting details. The new detective was even more mysterious than Sleeping Kogoro. He was famous for muttering to himself and figuring out the truth. His most famous line was:

"You're the culprit! Don't ask me how I know. I saw it."

The culprits: ...Are you psychic or something? I give up!

By the time Ginzo found a clue to the fish's whereabouts, Cang Zhuguang had already forgotten him. The fish was surrounded by a curly-haired cop, a purple-haired cop with shoulder-length hair, and even... Scotland, an undercover agent who'd already been executed.

Ginzo sneered: Well done, Cang Zhuguang.

At the same time, Conan suddenly noticed that a Porsche had been appearing near Beika Town a lot lately. Thinking the Black Organization had discovered he was still alive, he spent half a month terrified and unable to sleep.

That is, until the person in the car got out and abducted... Cang Zhuguang!

Conan tried to rescue his detective partner, tracking him down and charging into danger, only to break into a seaside mansion where a certain fish was living the high life and swimming in a luxurious, enormous pool.

Conan: Huh???

And the fish, having safely passed through his growth period and entered his breeding period, caught the scent again: Bro, I don't know you, but you smell so good.

Ginzo: ...Heh.

#Those years when Ginzo became a tool?

#Two people who originally had no threads become entangled with each other.

[Notes]

A pampered-by-everyone story, Ginzo pairing. The trashy little fish goes through a growth period, an evolution period, a breeding period, and a godhood period.

Seven-second memory loss trope. His memories will return in the end.

Ginzo's main plot and romance plot, fish farmer and fish food, with both of them having strong feelings for each other.

The souls of the Police Academy gang are summoned by the protagonist and can eventually be brought back to life. Platonic relationships.

Blurb written on 2025.8.10 at 02:38

Premise: Everything is in service of successfully coming ashore