MTL - Landing in the Fantastic World - Chapter 898 Underground mutation

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 day, Zhang Fan, a poor medical student, receives a medical system from the future. This turns him into a new shining star in the medical field. Along the way, he must face medical corruption, competition, and infighting from other doctors, and even find time for a love life as he strives for the top of the medical field!

- Description from Novelupdates

Ripped from a dead-end life and plunged into a world where danger lurks behind every smile, Xiulan must learn to thrive in a realm ruled by ruthless ambition and deadly secrets. When Li Mei dies in a traffic accident after another soul-crushing retail shift, she awakens in a familiar yet dangerous world—inside her favorite game, . Now inhabiting the body of Lin Xiulan, the scorned second daughter of a noble family, she finds herself thrust into a nest of vipers where her very existence is an offense to those around her. Armed only with her knowledge of the game and the wounds from a lifetime of dealing with entitled customers, Xiulan refuses to play the role of the family’s punching bag. Determined to rise above, she’ll need to master immortal alchemy, tame arcane spirit beasts, perfect her martial arts, and face off against her scheming sisters and stepmother. But in Arinthia, a land where power reigns supreme and the weak are swept aside, Xiulan must do more than just survive and fade into the background. With the knowledge of a devastating future that awaits the realm’s beloved Crown Princess, she’ll need every ounce of her modern wit and growing abilities to prevent a catastrophe that would ruin the entire realm—assuming she can survive her own family long enough to do anything about it. Only by transforming herself into a force of reckoning can Xiulan hope to protect those she comes to care about—and survive the darkness that awaits.

Having lived a normal life all his life and died without being able to fulfill his desire and when he’s given a task by a god, watch how he takes the protagonists girls while making it hard for the hero.