Eternal Life by Dual Cultivation - Chapter 13: Surging Undercurrents

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.

After midnight, you’re not allowed to enter the bathroom.

At exactly 2 am, there was a knock on the door.

A woman with disheveled hair and a bony figure always had her back turned to me.

Encountering strange events? Luckily, I can rewind!

This is a story of a reborn individual who navigates a world invaded by strangeness, carefully taking

- Description from Novelupdates

Reborn in the Naruto world, Shin Uzumaki finds himself in the doomed Land of Whirlpools. As a member of the Uzumaki Clan! Trapped in a world filled with war, betrayal, and unimaginable power, Shin’s survival seems impossible.. Until it isn’t!![Ding! Replication System Activated!][Daily Login Reward: Common Replication Card.]​​​​​​​[Newbie Gift: Perfect Sage Body—​​​​​​​Adamantine Sealing Chains​​​​​​​—​​​​​​​​​​​​​​Four Symbols Seal​​​​​​​]With the power to Copy any Ability—whether it’s the Kekkei Genkai or Rinnegan or Forbidden jutsu—Shin begins his journey to dominate the Ninja World. [First task: Save Kushina and prevent the destruction of the Uzumaki Clan.]

I traverse along the pathway of darkness and imagination…