He has a strong sense of justice and courteous. Even though he is considered smart by others, but isn't par with Shisu.
When Oshutoru comes to Kujuuri in order to form an alliance, Yashima is the representative that Oozen sent to greet them. At first Yashima suspects the envoy from En'nakamui is fake, and so he refuses to take Oshutoru and the others to Kujuuri's castle, asking them to stay in the village where Kuon and Haku first met. This is because Kujuuri's role is neutral in Yamato Civil War. But later, after being confronted by Anju, he agrees to take them to the castle.
He has a love and hate relationship with Shisu. Both of them try to win rulutieh's affection, which end up with Shisu beating him to an unconscious state.