R2-D2 is a droid from the Star Wars franchise.
Mysterious Rain Jack
R2-D2 makes his debut in one of Akira Toriyama's manga as one of the policemen in his second manga, Mysterious Rain Jack (1978), a Star Wars parody with a main character who looks like Kurikinton Soramame.
In Dr. Slump, R2-D2 sees Arale Norimaki run to school in the chapter "Arale on the Loose: Part 1". Arale is dressed up as him, while Senbei Norimaki is dressed up as C-3PO, in the cover of the chapter "The Invader from Space". The droid appears along with other Star Wars characters on the cover of the chapter "The Great Strawberry Panties Caper: Part 2". R2-D2 is seen again among the residents of Penguin Village in the special chapter "Kick the Can".
Dr. Mashirito's lab has the shape of R2-D2's head.