I am the sort of roleplayer who uses NPCs. These are characters that are not my main character, and are open for either roleplayer to use to advance the story. Sometimes you need outside characters (especially bad guys) to make a story - I am interested in writing stories with you so I am interested in sharing those characters with you. It is not godmodding to use an NPC or decide what they’re doing. I absolutely encourage it. NPCs are objects of the plot, and they should be able to be moved around with the same ease you can move around the key for that locked door or your muse’s jacket in the cold. You can even introduce NPCs yourself.
I will generally bold or italicise dialogue from an NPC to show that my muse is not the one speaking it, or make it otherwise obvious from context. If you are not comfortable using NPCs you need to tell me in advance of us starting a roleplay.