It is not easy to pull out a plug that is stuck to a power outlet especially if it has multiple plugs attached to it as it would require an effort to be exerted that can be real challenging, but now you can solve this problem if you have the Raku Raku easy plug that has a plug adaptor.
This adaptor is accompanied with ear like flanges on the sides and if you push it, it would by itself come out from the outlet, the flanges work as an eject button when pressed the plug would release itself. Only with a minimum effort you would be able to do the same thing even with the most difficult outlet.
The easy plug is made of plastic and has a recessed third non conductive prong present in the centre when you press the flanges the middle prong comes out, pushing against the outlet making it possible for the switch to detach automatically. This plug is very useful even for the old people or for the disabled people and is available in Japan for $14.