Question about NPC armors

[Odinfreya]

most armors are for your main character, or if you should do so equip them in a specific NPC/follower right? 

but for example i download this mod http://www.loverslab.com/topic/21547-sevenbase-conversions-bombshellcleavage-bbp/ the first mod is the tavern clothing. if i download this would all female barkeep would be wearing this armor? or its just for the character only mod?and only when i equip it to a NPC/follower would they wear it? Is there a mod that i can can change most of the world NPC armors rather thatn just the vanilla ones?  (particularly female ones since im in the adult mod section) ? its like a mod that changes the default in games npc armor/clothes.

thanks guys!