The End of the World: I Have a Deal with Zombies

[The end of the world + multiple female protagonists (zombie + human) + upgrade + pseudo system + base + decisive killing + not the Virgin] The apocalypse is coming, and zombies are everywhere. As a worker, Lu Yu happened to awaken to the trading system at this moment. As long as he completed the trading tasks of the system, he could get exclusive rewards, which could not only strengthen himself, but also give him rare treasures. What was even more surprising to him was that the system could trade with far more than just humans! In the face of constantly evolving zombies and various human-eating alien beasts, what should humans do? Behind this disaster, including the system owned by Lu Yu, there seemed to be deeper secrets hidden behind it. A post-apocalyptic story with multiple female protagonists is not a mindless and cool story, please support it.