Bruce Hyena is an adventurous friend of Geronimo Stilton who appears in the Geronimo Stilton book series.
Bruce has a secret crush on Geronimo's sister, Thea Stilton. He wears a red bandana. He is a sporty mouse that never misses out on exercise time. Bruce often forces Geronimo to go on adventures with him. He calls Geronimo a "cheesehead" because he's such a bookmouse. He is never careful and enjoys doing one-handed push ups. Every time Bruce does something wrong, he never feels bad. He is always energetic and happy. He does amazing tricks, likes to read novels and poetry and never misses a chance to get Geronimo into a marathon, races or any other kind of sports.