The author doesn't come right out and describe all of Yun Ok's character traits;
however, we can infer that:
She is patient and demonstrates perseverance by spending six long months,
slowly getting the tiger to trust her before she plucks out his whisker.
She is a sneaky and brave risk-taker because she is able to creep into the tiger's
cave and pluck the whisker without him knowing.
She is incredibly strong because she is able to fight off the tiger when he finds
her trying to take one of his whiskers.
She is smart and is able to trick the tiger into giving her one of his whiskers.