The triangular structure was built for the project, which is run by the non-profit Nippon Foundation and will see bathroom facilities built by leading Japanese architects including Pritzer Prize winners Toyo Ito, Shigeru Ban, Tadao Ando, Fumihiko Maki.
The project's launch was due to coincide with the now delayed 2020 Tokyo Olympics as part of an effort to improve the city ahead of the games. Tamura's toilet block was informed by Origata – the traditional Japanese method of gift wrapping – to reference the notion of hospitality.
"The renovation of these public spaces was conceived in the spirit of hospitality and as a symbolic gift to Shibuya's international visitors," Tamura told Dezeen.
"The ancient technique is not only an expression of beauty and etiquette but one of the highest forms of honor and respect when bestowed upon its receiver," she continued.
"In order to replicate the Origata technique and the precise folds of paper that embody it, I chose steel plates to create the exterior's structure and facade."
The triangular toilet block is divided into three with a wheelchair-accessible bathroom, female toilet and male toilet aligned in a row with the male toilet at the tip of the triangle.
Each of the toilets has a stall with a closing door alongside an area for washing hands with a sink and a mirror.
All three toilets are wrapped in a metal shell that Tamura is bright red. A colour that the designer chose to make the block easy to spot and would project a "sense of urgency".
"My first consideration was to not create a structure that would not just blend in with the surroundings," she said. "The location is industrial and lies beneath an elevated train station clad in concrete."
"I wanted to create an intervention that would be easily seen, recognised and telegraph a sense of urgency. All the things which typically accompany ones need to locate and use a public toilet," she continued.
"The colour red for me represents safety and immediacy and my feeling is that a public toilet is simply a utilitarian structure with one purpose only – it is not a place to linger or gather."
Tamura aimed to create a toilet that where all users feel welcome by focusing on safety and privacy. She hopes to "embrace the LGBT+ community" with her design.
"I believe that addressing the safety and privacy of users is most essential to a comfortable experience for everyone including LGBTQ+ community," she explained.
"When I embarked on this project, I decided that I didn't want to make a distinction between male and female when it comes to transgender," Tamura continued.
"My feeling is that if you identify as a woman, you should feel free to use the ladies room and if you identify as a man, feel free to use the men's room."
Other public toilets on Dezeen include a series of outdoor urinals, which caused an uproar when they were installed in Paris streets and a mirrored toilet block that was built on a scenic road in Norway.
Photography is by Satoshi Nagare/SS CO. Hiroko Hojo.