Hi, so sorry for the late reply.
The easiest way to see how outfits are managed for npcs is to look at the custom npcs in KinkyDungeonBones.ts, because thats where a lot of npcs have outfits and styles that match their name so you can cross search
A style is basically a collection of hair, body, cosplay, and face An outfit is just a fixed dress applied to the naked character that was generated with a style.