Unnamed fat scientist is a scientist that appears in the show. He is a member of the villain organization L.O.V.E.M.U.F.F.I.N., and is shown to have a monocle and a Russian accent.
He first appeared when Heinz Doofenshmirtz found L.O.V.E.M.U.F.F.I.N. In order to give themselves a shot in the public eye, the villains decide to participate in a dance contest. The fat scientist seem to be having bad dancing skills, and he and other evil scientists end up being smothed in debris by Doofenshmirtz's nemesis, Agent P. ("Nerdy Dancin'")
The fat scientist appears again during L.O.V.E.M.U.F.F.I.N.'s Second Inator Contest, where he laughs at Doofenshmirtz's low chances of winning the trophy belt. However, that doesn't seem the case when Doofenshmirtz actually won. ("Robot Rodeo")
During the L.O.V.E.M.U.F.F.I.N Pageant of Evil, he is seen doing a dance number with the other villains when they are about to vote for leader of the organization ("Bullseye!") The fat scientist is later seen attending the L.O.V.E.M.U.F.F.I.N. Summer Stock Festival Play, where he is seen applauding for Heinz Doofenshmirtz's fantastic entrance along with the rest of the audience, saying, "What an entrance!" ("Road to Danville")
Later on, he is one of the few scientists attending the L.O.V.E.M.U.F.F.I.N. First Annual Disservice Awards hosted by Doofenshmirtz in the Knights of Danville Hall, but it was interrupted by the noise that the O.W.C.A animal agents are making in the other room, which resulted a fight between the agents and villains. The fat scientist later appears again helping out catching many of O.W.C.A.'s agents after the members of L.O.V.E.M.U.F.F.I.N learned that Doofenshmirtz had successfully moved the Earth away from the Sun to an early autumn, as part of Rodney's plan to rule the world. However, later on, the agents were freed and engage into another fight with the villains, but it wasn't until Dr. Diminutive pointed out that it's exactly the same brawl back in the ballroom. Realizing this, the fat scientist and all of the villains decided to flee away for good. ("Phineas and Ferb Save Summer")
- "Nerdy Dancin'" (First appearance)
- "Phineas and Ferb Christmas Vacation!" (Pictured only)
- "Robot Rodeo"
- "Road to Danville" (Cameo)
- "Phineas and Ferb Save Summer"