I've Become a Genius Actor - Chapter 16:

When The Cute Kunoichis Spied on Their Teacher's Secret is a light novel written by Kazuma Kamachi and illustrated by Ryuushi Tajima.

The story takes place in a world where Japan never ended their isolationist phase, and agents from foreign powers are always threatening to steal the country's advanced technology. In order to combat this threat there has been a resurgence of ninjas that use Strategic Martial Arts, techniques that combine cutting-edge modern technology with a traditional foundation of martial arts and ninjutsu. The story follows Souha Sugiyado, a 17-year old ninja instructor and former ninja prodigy who was forced to retire from active duty by the wounds he suffered in his last mission. Souha's four students are all kunoichi who have all gained the rank of Elite Ninja, the highest official rank available to ninja. However, one day two Shogunate ninja approach him with the news that his four students have gone rogue and have stolen a portable modular nuclear reactor, and thus they ask for his help in bringing his students to justice.

One of the few self-cultivator who exist in this modern world; due to an unfortunate event, completely destroyed his body in an explosion. Using all his effort to save his primordial spirit, he ended up in an strange magical world and had to start all over again. From a fallen aristocrat to the Warlord of Chaos, this can no longer be summarise as legendary; this is the life of the God of War.

Regressor, Reincarnator, Possessor, Traveler, or Predestined. I will hunt down the protagonists that exist in the countless worlds and absorb their abilities.

Here lies the protagonist.

The continent’s hope.
The hero who will save the world.
The hero who currently has a hole through his chest!

With the Spirit of Earth, freed the Dwarfs and gained their trust.
Purified the contaminated Forest of Spirits and became the Fairies’ benefactor.
Resealed the Ancient Stone statues found in one of the ruins.
Exterminated the giant sea serpent that emerged from the sea.
Defeated the 47th Demon Lord of the underworld…

“Aside from assaults and murders there were other death related incidents as well as vandalism, arson, and etc…”

“S-spare me…”

Psh!

This was the protagonist.
But now he has died by my hands.

The mastermind leads and controls everything from behind the scenes.“Buy up all the food supplies entering Milan. Let’s starve them to death.”Cutting off the enemy army’s logistics is fundamental.“Give some money to that family and have them betray properly.”I scatter the enemy even before the war begins.I am the Black Merchant in Another World.