Tadashi Yamao is a student at the protagonists' high school and a friend to both Taku Morisaki and Yutaka Matsuno. He actively participates within the school environment, joining Taku and Yutaka in group activities. This includes his involvement in the protest against the junior high school trip cancellation, an event crucial to solidifying Taku and Yutaka's bond. Tadashi is present during classroom interactions and attends the school's cultural festival. His name, Tadashi Yamao, signifies "loyalty, fidelity, faithfulness" combined with "will, purpose," and "mountain, hill" plus "tail, ridge." His role is strictly that of a supporting character within the protagonists' social circle.