ALL MY WIVES ARE BEAUTIFUL ELVES - Chapter 24: Herald of lust

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.

When he woke up, Lin You found that the world had changed drastically.

Monsters of all races roar and bombard wildly, field magic cards form a deep sea out of thin air, royal tombs, skyscrapers, and trap cards are infinitely possible.

Duellist colleges and universities all over the country are rising, and the miracle secret realm is full of dangers.

This is a world where all people chase cards, and the era of card duelists shines.

- Description from novelbuddy

Shuu is a member of the literary club that can’t write. One day, he gets a mysterious message on his phone from a girl called Eina, and from that impulsive contact, they begin to exchange messages. They talk of things like their shared interest in novels and grow close. However, when they try and meet, they discover a shocking truth. Eina lives… not in the present, but five years in the past! How will their love develop, parted by five years of nights…!?

She is a descendant of Shennong with unparalleled medical skills and possesses a unique treasure. He is a handsome warlord who mysteriously goes blind and is sly and cunning. Crossing into another world, she becomes a six-year-old little waste. Through defying the heavens with summons and forbidden magic, she rises up in one fell swoop, showing a dazzling brilliance, looking down upon the powerful.When arrogant meets cunning and genius clashes with monstrosity, at that moment, the world trembles in awe!