Chapter 1
Prologue
There's an old saying: Even a one-inch insect has a zero-point five-inch soul.
At her grandfather's sudden remark, Nagi looked up from the insect terrarium.
Her grandfather, with his deeply wrinkled face, was smiling at her warmly.
Tell me, Nagi, do you know how big one inch is?
. . . ?
Nagi tilted her head in confusion.
It's about three centimeters. Look, about the size of your thumb there.
She stared at her thumb, her eyes wide in surprise.
. . . That’s big.
The old man chuckled at her candid reaction.
You're right about that. If there were an insect that size, it would undoubtedly be a fine specimen. One inch is just a figure of speech, you see. It means a little bit. So, one inch, in this case, represents just a tiny thing.
Hmm . . .
Now, Nagi. Do you know how much zero point five inches is?
Nope.
Zero point five inches is half of one inch. If one inch means a little bit, then zero point five inches is even less than that. In essence, the saying 'Even a one-inch insect has a zero-point-five-inch soul' means that even the smallest creatures have a tiny soul in them.
The old man looked at Nagi purposefully.
That said, if an insect's soul is half an inch, then the soul of a human is the same—fifty-fifty.
Nagi blinked in surprise.
Insect and human souls are the same size? Fifty-fifty?
Strange, isn't it? But, of course, insects and humans are quite different. Their forms differ, as do their lifestyles. The ancestors of insects and humans parted ways in the distant past, billions of years ago, in the ancient seas. Since separating so long ago, they have walked different paths. Over billions of years, insects and humans have drifted far apart until they became very different beings.
Nagi looked at the cricket jumping around the breeding case, then back at her grandfather's wrinkled face. Her grandfather versus a cricket. They were completely different. Totally different.
But you know,
The old man began to speak again.
Insects have always been by our side. Humans came to be just some two hundred thousand years ago, but by that time, insects were already thriving everywhere. Humans have always lived side-by-side with insects. We've had to deal with diseases spread by insects and had our crops ravaged. On the other hand, we've benefited from bees by collecting their honey and from silkworms by gathering silk threads. Sometimes we fight, sometimes they help us. That's the kind of neighbors insects have been to humans.
As he spoke, her grandfather seemed to be reliving the two hundred thousand years of history between insects and humans.
Whether you're looking at an insect or a human, the size of the soul is the same. Fifty-fifty.
The old man repeated his statement from before.
You see, no matter how different they have become, originally they were the same. No matter how much they've evolved, the size of the soul remains unchanged.
. . .
Nagi had no idea how to reply, so she just stared back at her grandfather. Meeting her gaze, he asked her a question.
Did you know that bad bugs possess people?
What?
In this town, there have always been the souls of many restless insects. Sometimes they are drawn to human souls and possess them. It's called being possessed by a bad bug.
Insect souls are drawn to . . . human souls?

Yes.