Mira and the key

[PandaLyambda]

Did anyone steal the key on Margery's table? Was it needed for something? (Because I didn't and now I can't figure out what that key would open - a door in a prison?)

[linkfire12]

Margaery's key only leads to a dialogue moment in episode 6 where she goes "Where is my key?" Giving to the option to either pretend to find it, tell her you had it for safe keeping (not neccessarily a lie, nothing indicates your stealing when you take it), admit that you took it, or do nothing.