- “A Junior Woodchuck is always prepared! I brought my lunch - peanut butter and sardines! I'm a growin' boy, ya know."
"I'd say you were three growing boys!”
- ―Doofus and Scrooge[src]
Doofus is a rather dim-witted and clumsy character with a positive attitude that is just as insatiable as his appetite. He exhibits hero worship for Launchpad, which frequently borders on the delusional (the relationship between Doofus and Launchpad, in many ways, mirrors that of Launchpad and Scrooge). Doofus is also marked by his strong moral compass, best demonstrated in the episode "Superdoo!", in which he uses paranormal powers to save the Junior Woodchucks from catastrophe, only to voluntarily relinquish them for the sake of hard work and friendship.
Doofus is a regular in the show often with Launchpad McQuack, acting as his sidekick. Doofus is a member of the Junior Woodchucks and is often shown wearing his uniform. When Scrooge travels 40 years into the future in the episode "Duck to the Future", Doofus has become trimmer and it's revealed that he is married to Webbigail. Since this future also involved Scrooge's nephews becoming money-grubbers and Magica ruling the world, this may not be definite.
Doofus reappears in the reboot, but his 2017's version is radically different from his original counterpart - rather than being a benevolent friend of the McDuck children, this version is a rich, spoiled heir who turned his parents into servants, and is one of the reboot's villains. He first appears in the episode "Day of the Only Child!", where Louie tries to befriend Doofus only to find out about Doofus' unhealthy lifestyle. Doofus was apparently not always this way according to his parents, but after the passing of his grandmother Frances (or "Gummeemama", as he refers to her), Doofus was named inheritor of her fortune and became inconsiderate, controlling, and obsessive because of it. Since he has everything his heart desires, Doofus views everyone as a possession he can treat however he wants, with the exception of his beloved grandmother, although Doofus becomes hostile when her likeness is threatened. When not exhibiting his selfishness, Doofus has a tepid, peculiar disposition and seemingly indifferent about how his quirks may startle others.
Doofus appears in the episode "Treasure of the Found Lamp!", where he traded a lamp Gladstone Gander bought for a blimp. He wanted the lamp to use as a gravy bowl, but then realised he could just make his father use his hands, so threw it away.
Doofus appears in the episode "Happy Birthday, Doofus Drake!, where he holds his Septleventh Birth-Anniversary party. It is attended by the Beagles, Flintheart Glomgold and a ventriloquist dummy, Mark Beaks and his son "BOYD", Louie and Glittering Goldie and throughout the night he ejects the guests who really aren't with families. Although he allows Glomgold to stay at first as he considered his act with his "son" soothing. Doofus does eventually kick Glomgold out after breaks the dummy. Louie and Goldie eventually expose Boyd as a robot, so Doofus kicks Beaks out of the party but keeps Boyd and orders it to kill Louie.
Goldie ends up stepping in front of B.O.Y.D. to get him to stop. To her and Louie's surprise, B.O.Y.D. shuts down and Doofus praises Louie and Goldie for passing the test. The whole ordeal was a test devised by Doofus to test their bonds of parenthood, just so Doofus could claim Goldie as his new "Goldiemama". Doofus relinquishes the gift bags to Louie and catapults him out.
Doofus encases Goldie in a glass prison and forces her to tell him stories. Louie eventually rescues Goldie and reappropriates B.O.Y.D.'s settings to treat the Drakes as his parents; the two Drakes happily embrace their new adoptive son. Feeling betrayed, Doofus throws a tantrum and threatens to sever his parents' pay, but B.O.Y.D. transfers half of Doofus' inheritance to his own bank account, which he generously shares with his new parents. Now reassured by a truly loving son, Mrs. Drake sternly informs Doofus that he is to be grounded indefinitely, for which Doofus vows revenge on Louie.