I'm probably not understanding the question, but I'll give a couple of options.
If the arrow is one that will not be pulled out of the quiver, you can make it part of the quiver model and either not rig each arrow (they wouldn't move other than with the quiver that way) or add a bone to each arrow that is a child of the quiver so that they can be animated easily inside the quiver (you could animate them without bones using muscle movement, but the bones would make it easier).
If the arrow is going to be pulled from the quiver, you are better off making it a separate model and adding it in the Choreography. If it were part of the character or quiver, it would be affected when the model bone for either is moved and you would have to do some counter-animating to compensate. You can use a "translate to" and "orient like" constraint to keep the arrow in the quiver until you want to use it, then you can set those constraints to "0".
The easiest way would be to have the quiver always on the character. If the quiver was part of the character, the belt could just be CP Weighted so that it moves with the character, then the quiver could be a single bone so that it can be adjusted when the character is moving around.
If the belt and quiver need to be adjusted by the character, you could make a chain of bones for the belt that are children of a bone that is the quiver. If you need automatic movement on the belt, you could put a dynamic constraint on the chain of bones or you could use cloth.
Shoot it at me.