Terezi & Caitlin Snow
Terezi never really heard of it either until she became blind and had to learn how to 'see' with her sense of smell and taste herself. It had definitely been an adjustment and took her quite awhile to get accustomed to this new way of 'seeing', but now she couldn't imagine living any other way.
"It usually is," she shrugged, picking up her walking cane which had two blades inside she could use as a weapon if needed. She usually left it at home, but since she was going to explore new territory, she figured she should bring it along. "It's pretty much just a game. You go inside the elevators, go to floors in a certain order, and you end up in some different realm."