So-Yoon's Grandmother is a graying old women With fine lines on her face. She is more often than not seen frowning or glaring at everyone except So-Yoon, Banya being the frequent target of her anger. She is almost always seen in her green jacket, blue jeans, and brown shoes.
She is generally a sarcastic old woman who is rather stern. Banya is typically the person she is at odds with, often disciplining him for his actions. She believes children should respect their elders, and whacks Ryo-Woon atop the head with rolled newspapers when he is speaking casually towards her (as if she were a kid like him). She is rarely stern towards So-Yoon.