In reality she's a hitman working for a giant, but top-secret organization of high-paid killers. On their IRAs they all say their musicians, but in reality they're assassins who kill for pay and sport. The entire organization runs itself like a gladiatorial fight-show with combatants earning the sum value of the next assassin up in their rankings when they kill that man or woman, and they themselves work up the rankings. Advancement ends when you're dead or you become afraid.

Or, she also may be bald and have a those grocery-store scan bars on the back of her head.