Mushi Sanban is one of the three secondary villains in animated short horror film Scooby-Doo: The Killer in the Barn and also a member of a biker gang. She is the younger sister of Kuki Sanban, the youngest daughter of Mr. Sanban and Mrs. Sanban, and also King Sandy's girlfriend. She is voiced by Tara Strong, who is well known for voicing Princess Twilight Sparkle in My Little Pony: Friendship is Magic and Equestria Girls film series.
Mushi, along with two bikers Vetvix (Vanessa Marshall) and Mr. Sanban (Keone Young), travels to Ponyville, and stops in a convenience store. In the store, Mushi takes to hassling female customer Applejack (Ashleigh Ball), having both Vetvix and Mr. Sanban restrain Applejack's older brother named Big Macintosh (Peter New). Having grabbed Big Macintosh's red wallet when he attempted to throw it to Applejack, Mushi taunts Applejack, making Applejack grudgingly ask for it back and address her as "Ms. Sanban".
After Big Macintosh mangles their motorcycles as revenge for troubling him and Applejack, Mushi, along with Mr. Sanban and Vetvix follow the two siblings back to the Sweet Apple Acres. Despite being reluctant to participate in her father's plan to burn down the Sweet Apple Acres barn, Mushi, after being reassure by Vetvix that nobody will get hurt, wanders off to look around. Going into the barn, Mushi nonchalantly begins toying with some of the equipment lying around, eventually climbing up onto the second floor. Finding a rope and pulled used to hoist hay, Mushi begins swinging from it for fun. Her father Mr. Sanban sees this and tells Mushi to stop fooling around so they can help Vetvix in her revenge plans. Unseen by Mr. Sanban, Mushi was ultimately grabbed by Fauntleroy Donaldson and pulled back into the barn, where Fauntleroy impales her to a barn rafter by the throat with a sharp pitchfork. Shortly, before Fauntleroy kills him too, Mr. Sanban finds Mushi's corpse, which Fauntleroy later moves. Mushi's corpse, along with the corpses of Mr. Sanban and Vetvix were by the authorities and taken away by the paramedics. In the deleted scene, Shining Armor (Andrew Francis) found her bloody corpse tied to a chair in Fancy Pants' mansion.