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Dōkyūsei (同級生, lit. "Classmates") is an adult-themeddating sim series created by ELF Corporation. The original Dōkyūsei, originally released in 1992 for the NEC PC-9801 microcomputer, is generally considered to be the forerunner of the modern dating sim. It was followed by sequels: Dōkyūsei 2 and Kakyūsei (下級生, lit. "Underclassmates"), both of which were also very successful. Kakyūsei was also followed by a sequel, Kakyūsei 2. There were multiple OVAs made from Dōkyūsei, a 12-episode OVA series (and three extra) from Dōkyūsei 2, and both OVAs and TV series from Kakyūsei and Kakyūsei 2.
Despite its title, most of the girl characters are not classmates of the main character.
The logo for the first game in the series.