Tumblebrutus is an ensemble character. He is one of the male kittens. He is rambunctious, though usually less-so than Pouncival. In London productions, he is named Bill Bailey. Much like Plato and Pouncival, the character in the 1998 film is commonly referred to as Tumblebrutus by fans despite it being a London-based production.
His three words are: “Chaotic, Imprudent, Funny” or “Tough, Buoyant, Touchy”
Tumblebrutus from the Hamburg Production