Tumbili is an older monkey, with wrinkles around his mouth and eyes. He has white hair, a grey face and ears with a pink muzzle. His eyes are dark brown. His body is off-white, with charcoal grey fur at the top of his back and brown fur meeting at the middle and continuing onto his tail. His hands and feet are grey.
Unlike Furaha, Tumbili is very serious-minded. He disapproves of Furaha's antics, and is hesitant to allow him to rejoin the troop. But he also has a hard time disappointing others, as seen when he cannot bring himself to tell Beshte the truth of what monkeys do when one is being a nuisance.
When they arrive, Furaha greets Tumbili excitedly. However, Tumbili isn't as pleased to see Furaha. Beshte speaks with Tumbili, who attempts to explain why Furaha had been forced to leave, but decides against it upon seeing Beshte's hopefulness. He thanks the two for bringing Furaha home, and Beshte and Ono leave.
Later, with Furaha unable to calm down, Tumbili confronts the excited troop member, stating that no one wants to play his games. Furaha gets an idea and waves farewell to his troop, telling them that he must be with his own kind, which confuses Tumbili and the rest of his troop.