alter ego

noun3

1. •
   An individual's alternate personality or persona; another self.

   • Clark Kent's coworkers finally discovered his alter ego, Superman.
2. •
   A very close and intimate friend.

   • GWM, 5'10", 175, 40, non-smoker, MCC-er. Good build. Int. in classical music, books, travel. Seeks alter ego with own peace for honest relationship. — 1974
3. •
   A corporation used by a person to conduct personal business in an attempt to shield himself or herself from personal liability, and which a court may penetrate by "piercing the corporate veil" to impose liability on the person when they commit fraud or injustice.