Are You (a) Christian?

One day, while I was on the way to a place in the center of the City by train, I stood beside a guy. I had a cross painting (tatoo) at my right hand like what Maria had in Ayat-ayat Cinta the movie. Unfortunately, that guy wasn't Fedi Nuril. Short story, we've got just a simple conversation:
Man: "Hey!"
Me: "yes?"
Man: "Are you Christian?", his eyes looked at my right arm which hung on.
Me: "No, you're wrong. My name is Lia."