Ah, yes... I've had problem with these types of people before. I think of, 'Character Copiers' like this: They think your character is awesome, so they made another that looks like you because they are too lazy to make a good character. It's not that hard to make a character honestly. There is PLENTY of options to choose from, there shouldn't be an answer saying, "I couldn't think of a cool design". This is why I love MassMarkings. Not everyone can see them, so decreases your chances of getting copied.
It tends to be more of the people with the original markings that are copying. Here was one situation where someone copied me:
Me: *Sitting on a rock in Ficho Tunnel*
Character Copier: *Sits next to me*
Me: *Sees them, feels a bit annoyed. I then whisper them*
"Hey, do you mind that you change your character a little? It looks awfully similar to mine, which makes me think you copied me. Not very happy with that." >.>
Character Copier: "No way, dude. You COPIED ME! I'm the real Summit (Name of my character). Plus I got more swag than you." What the heck?
Me: "You want to play that game? Check out my bio. Does it seem like YOU *coughs* a character copier *coughs* would have typed? NO."
Character Copier: *Quickly copies the bio, even though he has no idea what the words mean*
Me: "Just GO. I dop not like people who copy my character. It shows disrespect and it's nothing but rude."
Character Copier: "Whatever." *Blocks*
These types of things is NOT a game I like to play. I absolutely dislike them. Nobody has the right to copy a person's appearance without their approval. This is why I stick to MassMarkings and presets. Not everyone can see your look, therefore, less chance of getting copied.