Midna is the mother of Bobby Hill. She resides in the town of Greenhorne, typically looking out for her son's well-being.
Midna is an imp from the game The Legend of Zelda: Twilight Princess.
In the first episode, Midna gives Vinesauce his first quest: to save Bobby Hill, as well as an antique family heirloom. After Bobby's face was save, she thanks Vinesauce and gives him a reward of 200G.
Later in the third episode, she again asks Vinesauce to help find Bobby, worried that her son has wandered outside the town.