Tokyo (CNN)"Excuse me, are you hafu?" the taxi driver asked.
Anna, a woman of mixed Japanese and American heritage, was in a taxi en route to a party in Tokyo last year when she was asked that question, and says she had half expected it.
The Japanese word "hafu" -- or "half" in English -- refers to people who are ethnically half Japanese, and is now used more for multiethnic people in general in Japan.
Anna, who requested anonymity for privacy reasons, has a Japanese mother and a White American father, and spent her childhood in Japan, before moving to the US in her teens.
"I don't know how many hours I've spent telling my life story to strangers who want to fulfill their curiosity," says Anna. "It was getting to a point where I thought, Why do I need to share my biological background with someone I'm never going to meet again?"
Official figures paint Japan as an ethnically homogenous nation -- according to the 2018 census, 98% of the population is considered Japanese. People who look different, therefore, attract more attention than they would in a more ethnically diverse country such as the US.
In some cases, that's not a bad thing.
Many mixed heritage entertainers and sports stars are hugely popular in Japan. Well-known figures such as Vogue model Rina Fukushi and tennis star Naomi Osaka have given mixed heritage people more prominence in the public sphere in Japan, and globally.
For others, however, the apparent fascination with their heritage brings unwanted attention and can invite casual racism. Some who consider themselves Japanese say it leaves them feeling othered in their own country.
Mixed-race identity has a complex history in Japan.
Between 1639 and 1853, Japan closed its borders to foreign influence -- with the exception of Chinese and Dutch traders who came to the port cities of Yokohama and Nagasaki.
In those hubs, the derogatory term "ainoko" -- or "hybrid" in English -- was used to describe children born of a Japanese and foreign parent, according to Hyoue Okamura, a Japan-based independent scholar.
As Japan opened up and modernized during the Meiji era (1868 to 1912), it started cultivating its own brand of nationalism, promoting the country's racial homogeneity and superiority over other Asian nations. With the concept of Japanese supremacy came new terms to describe people of mixed race.
In the 1930s, the term "konketsuji" -- or "mixed-blood child" -- described the children of Japanese nationals who married locals in countries like China, Taiwan and Korea that Japan colonized. Those children faced discrimination as the government considered people from Japan's colonies as inferior to the Japanese.