This uniform is an example of the costumes worn in image clubs.
An image club (イメージクラブ,imējikurabu?), or imekura (イメクラ?), is Wasei-eigo that indicates a type of brothel in Japan similar to fashion health parlors. They differ in that image clubs are themed along popular sexual fantasies such as an office, a doctor's surgery, a classroom, or a train carriage. The prostitutes themselves, whose activities are usually limited to oral sex, wear exaggerated costumes appropriate to the setting and the desire of the customer.