Mōri Baien, Baien gyohin zusei, vol. 2, “Demon-head fish”

National Diet Library Digital Collections

Halloween is near.

Tiger or demon?

Today's star is the okoze.

Eyes turned upward, a back bristling with spines,

and a grumpy face peering out of the sand.

It hardly needs a costume to play a ghoul.

There is a reason for its fearsome appearance.

The okoze waits on the seabed to ambush small fish.

Its rugged body helps it blend into sand and rocks.

Its dorsal spines are venomous, too.

But why is its name written 虎魚—“tiger fish”?

Let’s start with the name.

Older forms include “wokoji” and “wokoshi.”

One theory holds that “oko” referred to ugliness

or a comical appearance,

while “ze” was an ending used in fish names.

Looking at its face, that makes sense.

But there is still no tiger.

So we turn to an old illustration.

Mōri Baien, a late-Edo painter,

drew an okoze under the heading 鬼頭魚: “demon-head fish.”

A fitting name for that face.

Beside the picture is a curious account.

Fishermen kept dried okoze in storage.

When storms persisted,

they brought them out and prayed to the mountain deity.

Why offer a fish from the sea to a deity of the mountains?

Some traditions describe the mountain deity as an ugly goddess.

An offering of an ugly okoze was said to please her.

This fearsome-looking fish was also a treasured gift to a deity.

Following the name and the picture,

we have met a demon and a mountain deity.

But why “tiger” remains unclear.

Tiger or demon?

Which shall we dress as this Halloween?