Yashiro was born on March 3, 1994, in Kamo District, Shizuoka.
[2][3] At first, Yashiro had some difficulty as an apprentice professional and even came close to being demoted in rank to 7-kyū; however, he started practicing regularly at the Kamata Shogi Club—a well-known shogi club where many strong amateurs, apprentence professionals, and even regular professionals would practice—and his results began to quickly improve.
[2][3][4] Yashiro defeated Yasuaki Murayama to win the 10th Asahi Cup Open [ja] in February 2017 for his only shogi tournament championship to date.
Yashiro was just twenty-two years old at the time which made him the then youngest player to ever have won the tournament.
[5][6] Yashiro's record, however, was broken the following year by Sōta Fujii who won the 11th Asahi Cup Open as a fifteen-year-old.