There's Something Wrong With These Demonic Women! - Chapter 240: Wife! Husband Wants To Challenge His Limits!

After breaking up with his girlfriend, he accidentally acquired a genius system and rose from there against the heavens, becoming invincible..

- Description from Novelupdates

Mimizuku, a small girl with chains on her wrists and ankles and the numbers “332” branded onto her forehead, wanders into the Forest of Night seeking to be eaten by a monster. However, when the ruler of the monsters, the mysterious and beautiful “King of Night,” refuses to eat her, she tries to formulate a way to convince him otherwise.

In a world consumed by monsters and chaos, survival is a cruel game of fate.Every year, the system selects a group of unwilling teenagers by lottery to fight, a death sentence Olivia didn’t ask for. Betrayed by her family and forced to fight, Olivia barely escaped death.In her near-death encounter, her system awakens….. only to deem her abilities “Useless”. But a chance encounter with a mysterious white snake sets her on an unforeseen path.Now, with the monsters lurking in the shadow, she has one goal: survive, grow stronger, and uncover the truth behind her fate.Survival is just the beginning. The real war is yet to come.

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.