Demon Sword Maiden - Volume 1, Chapter 15 – Details of the Samurai’s Test

In the end-French era, after countless calamities, the era of cultivation is coming to an end. The last combination of air transportation and evolution has evolved into the treasure board, which was obtained by the last practitioner in the end-French era, which opened up a legend of wandering heavens.

- Description from Uukanshu

She is intelligent, beautiful, calm, and professional. As the youngest chief forensic investigator for the past few years, her future was very bright. All of this, however, changed with a bizarre time-travel.

The ordinary world is not ordinary, ordinary people are not ordinary, and safe places are not safe.

This is a story of a passer-by male protagonist who is entangled by various girls with strange hobbies or even non-human beings while surviving in the cracks and opening a harem.

- Description from novelbuddy

A back-to-basics(?) monster evolution novel.