Awoken in a new world, everyone would panic at first. But he doesn't, or to be more precise, he can't. He has turned into an undead, or zombie. He was awoken in a tomb by a succubus, who believe he is the one who will brought destruction to the world.
After experimenting a bit, turns out he is a necromancer. He is able to summon undead, skeleton, even high level zombies. Now the problem is, what should he do? Sure, he is undead now, so killing a person is not uncommoon. But it doesn't erase the fact he was human, so some humanity is still left inside. Maybe he could save the people? By giving them workpower in form of the undead.
But with the succubus help, that kind of thinking doesn't hold for long.
In this world, light always triumph over dark, and so many demon are subjugated and forced into slavery. But they hold onto legend, that one day, their savior would arrive and save them, and bring an end to their suffering. From what the succubus said, he is not the first evil lord to be brought here. There has been numerous before him, some fail, some side with human. Only once, the evil lord won, and it was centuries ago.
At first, he is still unconvinced. But seeing how the human treat others, how arrogant they are, he decide that they are not worth fighting for
He will become an evil lord