Naruto: The Chosen Undead - Chapter 178 - no.177 Naruto

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.

Three thousand years of bowing down to the Demon Lord, I would rather be a mortal than a celestial being when looking back, but for her I will… become one who controls life and death!

Transmigrating to a lawless person and then directly upgrading to a little brat’s stepmother. Xiao Ting said, “Crap, there’s no need to even give birth to a child. God, I love you so much …”

- Description from Novelupdates