Grassroots Rebirth: Future Harem and Hegemony

Main plot: I was a grassroots who died in the future world war, but was reborn back to before the war. While I was pretending to be a pig and eating a tiger, I used anti-routine training methods to quickly improve my skills to the full point. I was also building my own harem, dealing with various conspiracies from rivals and other villains, and resisting cross-border invasions. The goal was to become the overlord of one party in this troubled world and protect the people around me. This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.