The Dragon King's Harem System - Chapter 298. Walking Around The Palace I

I was reincarnated into another world, and I’ve brought the Horadric Cube from Diablo II with me.
Being a knight is cool and all, but being a wizard is pretty neat as well.
So, which one will it be?

- Description from Novelupdates

She, a 21st century mercenary queen, had crossed over into a tragically betrayed body of a waste. Waste? She will show them what it means to be a waste! Betrayed? With the Ancient Manual in her hands, she will astonish all the despicable men and cheap women!

Year 2056, in a city in the Yuan Jiang Su Jin area. On top of a ruined, shattered six story residential apartment sits a teenager wearing a combat vest, militaristic trousers, and alloyed battle boots. On his back is a hexagonal shield and equipped is a blood-shadow battle knife. He sits there silently on the edge of the roof. At this time, the sparkling sky was shining and there was a refreshing breath within the air that blew towards him. However, there was only silence within the ruined, deserted city, with an occasional howl that makes your heart skip a beat.

A mysterious natural phenomenon caused the Earth to be plunged into darkness. The world turned into an endless bloody chaos and mankind is on the brink of extinction…