Reborn as an Extra - Chapter 13 Was Lia Always A Chatterbox?

The protagonist of the collapse of the three former civilizations is Dr. Mei. What is the end of logic, the strongest brain, super intelligence, this is the story of the strongest scientist of Honkai with knowledge of the moon becoming the god of science!

- Description from novelbuddy

Lugis is an adventurer who accompanies the Hero’s team party. However, every day he has to fulfill tasks that are not pleasant at all. In addition, he is oppressed by the other members of the group. The only reason he remains on this journey is because of his childhood friend, Ariane. But she is fascinated with the team leader known as Hero. One day a shadow figure appears and tell Lugis, “Let me give you a chance. A chance to redraw your life.” And so, Lugis is given the opportunity to be sent to the past to restart his life.

The mortal body, metamorphosis, longevity, immortality, and eternal life. These five realms, step by step, reveal themselves in front of you. As a normal person, how can one try step by step to reach and open the door to eternal life?

Between the heaven and the earth lies the mortal body, the mysteries of metamorphosis, freedom of longevity, the power of immortality, and the hope of eternal life. A story filled with endless new magic, a new world of immortal styles, people, demons, gods, fairies, magic, kings and emperors. A world of love and hatred, revenge, and mystical battle, all in “Eternal Life.”

- 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.