Prince Hisahito, in contrast to his sister Princess Kako?
Witnessed "walking to school" in plain clothes.
According to the magazine Josei Jishin:
On weekday mornings, businessmen and students on their way to the station do not pay attention to a high school boy dressed in a dark blue parka and long pants.
But he was Prince Hisahito, the eldest son of the Akishino family.
This spring, Prince Hisahito enrolled at the high school attached to the University of Tsukuba.
Since this was the first time for the University of Tsukuba High School to admit a member of the royal family, the security system had been tightened at a rapid pace.
A prior application is required for non-students to visit the school, and the grounds are surrounded by barbed wire to prevent intruders from entering, and other measures have been put in place to prevent suspicious visitors.
A guard escorted Hisahito to school as well.
However, the atmosphere was not at all somber.