you could always wear a tang top with a gauzy long sleeved over blouse.
you could tell them it's none of their business
you could put vitamine e oil on them which helps with scarring some
you could look at them mysteriously and say "I could tell you, but i'd have to kill you" in a NYC mob accent.
you could call it decorative body art - if they are lines you could say it's representational art.

kiya