Wudang Sacred Scriptures - Chapter 18

18 years have passed since I was born as Allen, the eldest son of an earl in this world, while still retaining my memories of the present world. This world is peaceful and a stable society. The only extraordinary thing is that I was reincarnated into a world that is lenient on the existence of concubines. I selected a silver-haired maid as a sex slave and second wife candidate from among 10 candidates after a strict fellatio practical exam. I then lived an erotic life at home and at school as an attendant, but my reincarnated life is so fulfilling that I'm worried it will explode, as my busty childhood friend, a noble girl who was unsuccessful, ran for the third wife candidate, and my stepmother, who was my virgin partner, was sold off.

When he returned to the World of Martial Arts, the game was filled with blood and battles! Chen Kaixin had chased after the footsteps of the one emperor, two empresses, three princes, seven dukes, and thirteen aces for three years, but during the eve of the Sword Among Us tournament in Mount Hua, he was ambushed by evil bastards, and was killed so much that his level dropped to that of a newbie. He completely lost the chance to join the ranks of the powerful players in the game! In great disappointment, Kaixin quit the game and got drunk so that he could forget his sadness, but during that stormy night, Chen Kaixin found that he had actually dreamed for a total of three years, because when he woke up again, he woke up to three years ago, when he was still a student.

- 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.

After the battle, the beautiful senior sister shyly raised her face in front of you and slowly closed her eyes. At this time, you…

Eh? The choice this time was too simple. Of course, it was four.