How much blood will the Inter-labia pad absorb?
The Inter-labia pad is small, but it is meant to catch the "gush" that you experience during menstruation. It prevents all the blood from getting onto to your pad.
Should I always back up the Inter-labia pad with a cloth pad/menstrual cup?
Preferably, yes. If you are using the labia pad just for white discharge, then you need not. But if you are using it to absorb menstrual flow, then you should back it up with a panty liner, pad or a menstrual cup.
Will the Inter-labia pad stay in place?
The Inter-labia pad must be folded and placed near the labia; therefore, it may move its position if not properly placed. It is advised to ensure that it is well-placed.