First of all, you talk about Kingmaker, not Wrath of the Rightious.
In WotR you can actually become a lich and have undead minions.
You also have Dhampir race, a half vampire who is healed by negative energy and harmed by positive.
In Kingmaker the closest thing to this is a sorcerer with the undead bloodline.
You gain several death related spells and you can use mind affecting spells against undead like they were humaniod (normally undead are immune against mind affecting spells).
Note that undead use charisma instead of con for hit points and there is a spell that lowers charisma from enemies a lot.
Just be a single class human sorcerer. Multi classing means you get weaker at casting spells and thats what sorcerers do best.
Max out charisma and chose (greater) spell focus and (greater) spell penetration for your spell school of choice. I would advice necromancy and conjuration. If you chose conjuration use also the feats that improve your summons (works only for summon monster spells, not necromancy summons).
Pathfinder is based on DnD 3.5E but there are some differences.
In NWN2 it made no sense to make a sorcerer without the arcane scolar prestigue class. The only good thing sorcerers get are spells and everything that continues their casting abilities and gives them something else (improved meta magic feats in case of arcane scolar) makes them better.
In Pathfinder most classes get something useful as they level up ( e.g. bloodline spells,feats and powers for sorcerers) and all classes have archetypes (subclasses) that alter several class abilities so that a single class char almost turns into something that used to be a multi class char in DnD 3E.