Harem Emperor In The End Times

Ryan loses his sister in accident, however due to supernatural circumstances he wakes up in an Parallel World before the death of his sister. But before meeting his sister the Zombie Outbreak broke all over the world... After killing 10 zombies, Ryan activated the Apocalypse Overlord System. Doesn't this force him to conquer the world and start his own ideal country? So, Ryan conquered all the way, starting from A City, and embarked on the path of a Apocalypse overlord. Want to survive? Call me master first. No matter you are a high-ranking official, a celebrity singer, a policewoman, or a socialite, you are just under the rule of Ryan. If you want to survive, just be a good girl...