Necromancer in training

When John's home city is attacked by a necromancer, something inside him breaks. A little bit of his sanity and normal reasoning skills are lost. Though instead of joining the forces of good and trying to track this necromancer who killed everyone he ever knew, John instead falls in love with the art of necromancy and becomes determined to master it.

Being neither talented with the art, or even properly understanding how it works, the work is slow. But who cares when you can turn into a lich eventually and live forever?