MTL - Night of the Nine-Tails, I Punch the Tailed Beast Ball - Chapter 557 exposed

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.

Once all people received Souls and incredible powers. Some were lucky enough to obtain the Soul of an ancient and powerful creature, but fate was not favorable to all.

The world began to change, and creatures evolved. But, it was not the beginning of a new era. It was the end. A couple of months later, a dark mist appeared and destroyed the world. It was a dictate of destiny from which no one could escape.

Wain Norheim was the world's best assassin and the only one who didn't get a soul. However, he was destined to gain the power to confront fate.

Escaping through a portal into another world, he unknowingly began the apocalypse. Even the world failed to expel him.

Yu Shanshan, who has been tyrannical and lawless for 20 years, suffered retribution at the age of 21. She changed from a little ballet princess of 45 kg to a poor and fat one of 90 kg.. Apparently, eating was the most important thing in her life. Her success in losing weight was far away.

However, one day, the father of her child who had disappeared for four years came back. From then on, Yu Shanshan was forced to embark on a diet that was worse than death.

- Description from Novelupdates