MTL - Silly Spring Attack - Chapter 19 Invitation for twins

In the era of steam and mystery, becoming a correspondence student at the Thaumatology Academy was something Shad never thought of.

A whispering voice rang in my ears, who was reciting the poems of foreigners——

The old gods and aliens,

When the brassy rings of fate turn,

The golden runes are flickering.

steam surge,

the fire flickers,

Relic echoes,

The old gods revived.

The outstretched hand after the thick fog,

Pull back the hazy curtain of the crazy age.

Guests from afar explore the lands of the Old Continent,

Striking the melody of the next era.

Came here through the gate of time,

Shad put down his suitcase,

Look at the silvery moonlight overhead.

- Description from novelbuddy

He was not a human since no human is aware of himself even before his birth.

He has no blood and no heart, but emotions?

He does have feelings, but can he express them?

Why was he called a Devil’s Spawn at his birth?

Why did they cut away his arms and a leg?

Why did no one ever visit him for years?

And why does this emptiness... feels so... just so familiar?

Why does the Void feel so... full?

Who is he? Or rather... What is he?

When an S-class elite assassin-raised captain of a special ops suicide squad comes home from a high-stakes Africa mission, he finds himself offered something that could potentially set him up for life- a curious assignment that he could use to finally exit his days of war and slaughter.

Leiyin accidentally crossed into the One Piece World, and accidentally obtained the Naruto System.