"Secret Alignment System"

My most preferred current version of fantasy dungeon games is BFRPG, there are no alignments in that game. This frees players that want their characters to be heroes to act as heroes and those that want to be anti-heroes to fill that role without worrying about cosmic retribution...right? Wrong.  Nope the universe is still watching but a character's relationship to the cosmos emerges in play.

Where does that leave NPCs?  Well they get an alignment in my notes. That alignment is however a bit more about generic outlook, faction involvement and interaction with others as opposed to cosmic ethos. The underlying model builds off of fairytales. Is that critter likely to eat you? Is that goblin wicked or just greedy?

I assign NPCs and monsters one or more attitudes and motivations:

Benevolent - Hey it's happy and friendly most of the time!

Honorable - Driven by expectations of honor, tradition, and society. Bargains are respected. 

Pious- motivated by their faith and have it govern their daily behavior. The broad dictates of their faith can create a wide range of reactions in this broad category as Cultist of The Purple Spider have a very different code from the Sword Saints.

Timid- It's not dangerous and will seek to disengage from conflict most of the time. 

Selfish- motivated by self-interest but has no outward desire to harm others. Selfish individuals typically put themselves above other concerns. This can create internal conflict that they are forced to confront.

Greedy- The acquisition of wealth motivates everything. They are loyal to their purse strings and only honor bargains to maintain the promised cash-flow.

Aloof- It really just doesn't care about the world of men and wants nothing to do with it. Some Aloof creatures will go out of their way to avoid others, and some will react with shocking cruelty to those that interfere with their plans.

Hungry- all it cares about is eating. Doesn't try to make others suffer but if it's a carnivore you are on the menu if you aren't close friends.

Hostile- aggressive and seemingly always looking for a fight. Does not tolerate the presence and behavior of mannish folk. Hostile creatures are dangerous to interact with.

Wicked- nasty and evil. Rules are made to manipulate others and aid in the destruction of the weak and innocent. Wicked creatures will be scheming and unwholesome but are not always overtly dangerous. 

<faction name>  - this indicates membership in a faction and this involvement provides motivation to the NPC.

In an NPC write-up the first attitude is the most important with up to two others governing that.

Examples:

Gufflebore Dwarves, A: Greedy, Honorable - these fellows are motivated by greed and lust for gold but are likely to honor tradition and negotiate if proper procedures are followed but their palms are always welcoming of a few extra coins.

Muck Ogre, A: Hungry, Hostile- always looking to fill their maws and you my friend are on the menu. They can be diverted or distracted by a ready supply of food as the favor eating over fighting.

Willow Elves, A: Seelie, Aloof, Benevolent- they are apart from the world of men and involved with the rulings and politics of the Seelie court above other matters. They are oddly helpful and will be kind and helpful to individuals as the situation mat dictate.

The Weeping Sisters, A: Hungry, Unseelie, Hostile - these phantom elfin maidens seek to feed off the essence of mannish folk.

 The "secret" here is not every NPC wears their alignment like a badge but interaction during encounters will expose and govern behavior of NPC in relation and reaction to PCS. A PC that frequently battles members of the Seelie court would be dealt with a hostile manner by those aligned with that court. Aloof creatures will not seek to engage with PCs unless PCs push the matter. 

There is no cosmic balance written into this but there is a system that governs interaction and expectations to those that learn about the attitudes and alignment of others.