Although Yasuo's half-brother Yone is the exact opposite of him

What made his peers grit their teeth was that Yasuo showed his extraordinary talent and became the only one among the disciples of several generations who received the attention of the elder Soma. He was the last master of the legendary swordsmanship. The old man saw Yasuo's potential, but the impulsive disciple rejected his exclusive teaching like an unrestrained whirlwind.