Dupper was a baby Guosim shrew who was captured by an adder; Mad Maudie, Log-a-Log Luglug and Asio Bardwing pursued the snake to rescue the infant. Asio Bardwing fought the serpent and slew it, not believing it was a poisonous adder; he was bitten several times and died of the injuries. The shrewbabe Dupper was returned to his mother, who, when told of the events of her son's rescue, was greatly moved. She renamed her babe Asio after the owl that had saved his life, to the unanimous approval of the Guosim. Dupper was a minor character; nothing else is known.