Rules of Survival in the World Invaded by Monster Girls

[80 points·Licorice·Monster Girl] A very exciting theme, similar to the background of the intersection of celestial bodies in The Witcher. The world is invaded by various monster girls. Because monster girls can only produce monster girls, the number of men in the entire world has plummeted, and men have become a scarce resource. The protagonist wakes up in the future world. Because of the world view, he begins to be sought after by various monster girls. Fortunately, he has a plug-in. He can unlock the monster girl illustration book through observation and interaction, and purchase various items and abilities in the mall to improve his combat effectiveness and fight against monster girls. Overall, it is a man's final fantasy, but with the recent popularity, I feel that the author's writing is still too conservative.

Standard version of light novel, fantasy version (dog head)