This is an idea of future technology, a new communication for next generation.
Coming out one day without being in the mood even for talking to others, you can inform others about it You can do it just by creating a halo of colors all around you. By doing so the others would treat you better and patronize you. Every color would be agent of one inner emotion. People can show or hide it optionally for instance pink equals happy, purple represents anxious and orange for cheerful.