Assuming that you displaced all the electrons in the same direction, you'd produce a 1 cm electron cloud on one side of your body, and 1 cm of electron-deficien

Assuming that you displaced all the electrons in the same direction, you'd produce a 1 cm electron cloud on one side of your body, and 1 cm of electron-deficient matter on the other side. If you could somehow maintain that configuration, you'd have a capacitor storing an enormous amount of energy, so it makes sense that the mass would increase.