The Braille on khatun's face is in german. They translate to "angel" and "shepard"
Khatun only appears in two episodes. She appears in episode one. OA visits her after drowning. Khatun attempts to convince OA to stay in the afterlife. After OA persists, khatun takes her eyesight and allows her to return. In episode four, she tries to convince OA to stay once again. She reveals that she has wings, and gives OA her name. She also gives her a bird and tells oa to swallow it whole. Khatun tells oa the bird has a price, which isn't revealed in season one.