I Want To Have A Yandere - Chapter 31: Exam Part 5 Reassurance

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

- Description from Novelupdates

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 Orion is mysteriously transmigrated into a primitive world where sex and other goods and services can be bartered for, he is determined to make the most of his second chance at life.

But as he delves deeper into this dangerous world filled with temptation and magic, Orion must use his wit, charm, and thirst for adventure to survive and make the most of his second chance at life.

Growing up in a place where the rule of the jungle is law, the simple yet cunning Shaar is thrown into the chaotic world of war and political turbulence. After a chance meeting with a mysterious young girl, his destiny is forever changed as he embarks on a journey, joining the Byzantine army and climbing its ranks. With his bizarre beauty standards, will he ever return the affection of the girls that will follow him? Will he ever learn about his real parents? What lies ahead of him is a journey of strange humor and adventure.