Princess Aiko, the only child of Emperor Naruhito and Empress Masako, turned 19 on Tuesday while attending online classes at her university as a first-year student amid the novel coronavirus pandemic.
The princess, enrolled in Gakushuin University in Tokyo, has been taking part in virtual lectures since the start of the academic year in April. In October, she visited the school and met her professors and classmates face to face for the first time, according to the Imperial Household Agency.
"I cherish the joy of gaining knowledge and would like to participate in a lot of things in university," she told reporters at the time.
The princess, who is studying Japanese literature, has also been taking language courses in English and Spanish, as well as sports and health sciences, according to the agency.
At the school, where her father also studied, she joined a campus tour and attended a briefing session on future courses.
While in high school, the princess expressed interest in classical Japanese literature.
She wrote her graduation report on cats and dogs described in "The Tale of Genji" and other classic novels. Her piece was twice as long as the standard set by the school, according to the agency.
The princess takes care of her dog "Yuri" along with cats "Mii" and "Seven." She is also looking forward to visiting Ueno Zoological Gardens in Tokyo, where an elephant, sent to her by Thailand to celebrate her birth, had a baby in October, the agency said.
Due to the pandemic, she refrained from going out for a summer rest and on other occasions, instead taking walks with her parents at the Akasaka Estate.
In November, she watched on TV her uncle Crown Prince Fumihito be declared first in line to the throne in the "Rikkoshi no rei" ceremonies. It provided her with a chance to learn more about the imperial family's history and traditions, according to a close aide.
Through daily interactions with her grandparents, former Emperor Akihito and former Empress Michiko, the princess has been learning what is to be expected of her as she comes of age next year, the aide added.
Japan's imperial household has been shrinking ever since the enactment of the 1947 Imperial House Law that stipulates only men in the paternal line can ascend the Chrysanthemum Throne, currently leaving only three heirs. Women must also abandon their royal status upon marrying a commoner.
After turning 20, the princess is expected to perform official duties as an adult member of the imperial family.
The government is considering ways to enable female imperial family members to engage in public duties even after marriage by giving them honorific titles.