Briar is a short, slender, young, and beautiful girl. She has pale skin and long black hair.
From what is written about her, Briar is known to be quite resilient. Despite her burns and lashings from Hybern’s soldiers, she was able to walk without Azriel or Feyre’s help when both of them were too injured to move.
She also gave her last scraps of clothing during their escape to help Feyre’s wounds.