That be dragons at Rose City Comic Con and many many people dressed up in cosplay for the event.
Good etiquette for picture-taking is to always ask to take a picture. Yes, people dress up and cosplay, but they are attendees as well! If you’d like to take a picture of someone at events such as this, please ask, “Would you mind if I take my picture with you?” It’s just good manners.
See you at the con!