Reborn: Revenge of the Concubine's Daughter - Chapter 37 - Selling her coffin

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.

Year one of the New Era, the Demon King was defeated by the Hero, divided into thirteen parts, and sealed all over the world. Only the soul can reincarnate and be reborn.Year sixteen of the New Era, in the tavern of a small town on the border, a young maid named Mohe sees a middle-aged man who only brags to deceive people for drinking money. However, she knows better than anyone that he was the Hero who defeated her and split her into thirteen parts.“The former Demon King is now wearing maid clothes and working as a server here?”“The great Hero sir, instead of being affectionate with your harem group, you bark here like a stray dog, deceiving for food and drink. How is that different from a beggar?”

I just lost myself in the deep and shallow temptation of her.
——by Jiang Hanyu
Everyone knows that the person Nan Gao doesn’t mess with is Jiang Hanyu
She is arrogant and fierce, relying on beauty, a proper little overlord in school
Everyone thinks that the best relationship with Jiang Hanyu is to call him brothers.
But one day, someone found that Jiang Hanyu was holding the hand of the goddess of coldness in the class and lowered his eyebrows after class.
Unruly girls become gentle and charming
He also said in an unbearable and irresistible voice, “Si Nian, will you give me a kiss?”
Then everyone knew that the best relationship with Jiang Hanyu was…

TIPS:
1. The Great Demon King X Miss Gao Leng
2. Campus text

- Description from novelbuddy

Jiang Chen transmigrates into a different world which is full of monsters and demons. And through Class Transfers, humans could clear dungeons, level up by slaying Monsters, gain experience, and enhance their strength to protect their homeland.Jiang transfers to a D-level swordsman and awakens a system.【Hundredfold increase ····· Amplification successful】【Sword Qi Surging Amplification loading ····· Amplification hundredfold】“Is he really a swordsman? Why can his Sword Qi reach a terrifying 40 meters?”“He definitely isn't a swordsman, his Sword Qi can defend automatically.”“What the hell is True Qi?”