MC finds a female android and she becomes his companion wielding a sword, think he becomes stronger by killing zombies I remember him finding some child zombie in a lab that ended up being released by a old female friend and her boyfriend and they ended up dying
Era of Disaster, not quite good in my opinion, i'd rather read the cringe worthy story of YZ (God and Devil World).
Definitely, If you're tired of apocalypse mc's saving every girl they meet, this is is definitely for you. The mc is a bona fide asshole.