Normally slipper is used by the meaning of the footwear slipper. But it can also relate to "being a slipper", which means to
obey almost
everything you're asked to do. By other
words you're extremely dutiful if you're a slipper.
"Robert is my slipper since he does
everything I tell him to do."
"Oh, stop it! You
don't have to be my slipper all the
time! I can do my dishes on my own."