Ability to Categorize NPCs

I have a growing list of NPCs in my campaign with over a hundred npcs on the roster now. I would love the ability to categorize the npcs within that list. Like being able to click on one in the npcs list and have a drop down list of options you could add entries to of categories that would seperate npcs. Like “Town of Dragon Peak” “Standby Party Members” “City of Baldur’s Gate” “Flaming Fist Mercenaries” This would make finding npcs on the list easier when dealing with significant numbers of them.