— The fat robber, The Seventh Mystery
The Robbers are two minor villains in The Doraemons Special Vol 3, Chapter 8: The Seventh Mystery. They planned to break into the school at night to steal valuable items but are foiled by Nobita and Matadora. They consist of a skinny man and a fat man.
Plot
The robbers plotted to steal the valuable items from Nobita's school at night. Nobita and Matadora, who used the Time Machine to prove the truth of the Seventh Mystery, sawy them trying to open the window. The two decide to use the Seven Mysteries of the School to foil the villains' plan.
The fat robber is enraged.
They succeed in making the thin robber loses consciousness (with Mona Lisa's portrait did the job) and scaring off the fat robber on the second floor. However, Nobita failed to completely scare him off with Big Light causing the fat robber to recognize that he is the one who pretended to be a floating head ghost.
Enraged, the fat robber reveals a knife and proceeds to chase Nobita down the stair to kill him but is saved in time by Matadora who knocks the robber to crush on the stair. The robber however, manages to regain consciousness and attempts to kill both Nobita and Matadora but is finally scarred off when the Big Light was used by the past Nobita who unknowingly enlarges him. The robbers are arrested afterward while still claiming about the giant Matadora and the Seven Mysteries of the School.