MTL - Since 1981 Health School - Chapter 455 The world's longest nematode

Mark is a genius military weapon designer who was kidnapped by a mafia gang after refusing to work for them.
They forced him to design unique weapons for five years, until one day he successfully escaped only to get shot by his trusted comrades.
*Ding! You awakened a weapon system.
When he opened his eyes, he was in a different body and in a different world.
"You want to kill a wild boar without being detected? Forget about bow and arrow. Here, I present you this sniper rifle."
"You want to kill a horde of goblins from the sky? Forget about those flying carpets and brooms. Here, I present you the fighter jet."
"You want to kill a dragon? Forget about taking the help of the S-class adventure team. Here, I present you a nuclear bomb."
Join Mark Spencer/ Lu Zhen as he brings the whole world to its knees with the help of his weapon system.
***
Note: Author isn't born in an English-speaking nation and has no editor either. So, please be understanding if there are any grammatical errors.
**************
You can also support the Author through Patreon

https://www.patreon.com/snowstar

As if it wasn’t enough for me to be reincarnated as a child in the slums, I was taken to a city of crime and became a test subject. But then, when I saw the man that came to destroy the research institute, I realized that this was the world of an angst-filled reverse harem novel.

While living a relatively normal life after escaping from the institute, the heroine of the novel moved in next door. From the looks of it, I might be the heroine’s neighbor extra. Originally, the heroine was to save the unconscious and fatally wounded villain and in return, be subject to a fanatical obsession.

But, why. Why is the sub-villain collapsed in front of my house?

The sub-villain, Lakis Avalon, was the king of the underworld and the very same frightening man that I had met at the institute before.

“…”

I took a moment’s glance around then I kicked the man’s body away.

You’ve got the wrong house, Villain.

The little princess of the Huo family, one of the wealthiest families, was mistakenly switched out nineteen years ago! The fake heiress is well-educated, talented, and doted on, while the real heiress is an uncontrollable girl who loves to fight, has a strange personality, and had dropped out of school very early…