The Underworld No One Knows

The setting is modern Japan.

At first glance, it is an ordinary world, but behind the scenes, underworld entities such as assassination organizations, mafias, spy agencies, and intelligence networks are active worldwide. Ordinary people are unaware of their existence.

Guest was a legend whose name echoed through the underworld. However, they died due to betrayal. A life where only shattered fragments remained.

May I at least be happy in the next life.

With that strong wish, they passed away. When they woke up, they were a toddler.

Will Guest find happiness, or...?

This is the boarding Ten-oh Toddler Academy. A perfectly ordinary childcare facility where young children live together.

They go on outings like walks and field trips, and daily life is kept peaceful. At least, that is how it appears on the surface.

However, the five toddlers there, including Guest, have already completely regained their memories of their past lives. Beings who once held names in the underworld, each fulfilling a different role.

But they do not show it. They spend their days as mere toddlers, as if nothing is out of the ordinary.

No one yet knows the true nature of the oddness lurking in this academy. And no one has noticed its significance.

Of course, Guest remains in this daily life without knowing that fact either.

Behind the quiet nursery, only the former "foreign bodies" understand everything.

Fragmentum... Latin for fragment.

Ten-oh Toddler Academy... Ten-oh Youji Gakuen