Midbus is the secondary antagonist of Rise of Fawful. He is Bowser's rival and Fawful's loyal minion.
Not much is known about Midbus, as he only has one line so far, but it's pretty obvious that he's loyal to Fawful, as he saves his life when Bowser Jr attacks him, and immediately obeys Fawful's order to knock Junior out.
Midbus first appeared in Rise of Fawful where he helps Fawful to invade the airship. When Bowser Jr. attacks Fawful, Midbus grabs him by the tail and beats him up. Then he uses a bodyslam attack, to knock Jr. out.
Dannywaving has stated that Midbus is the hardest character for him to model.