The main protagonist of the story. He moved from his home in rural Hiroshima to his aunt’s dormitory in Tokyo to change himself. While checking out his new high school, he sees a beautiful high jumper practicing and falls in love at first sight. By chance she happens to be his next door neighbor, Suzuka Asahina. Yamato is clumsy and has a carefree attitude, which often gets him into comprising situations. When the need arises, he can become focused and determined. He is exceedingly clueless when it comes to girls and their feelings. Although not the best in academics, he discovered a natural gift as a sprinter, and joined the track and field team.
During his senior year of high school, he became a well-liked and respected track captain. Even though he did not achieve his goal of becoming first nationally during high school in the 100 meters, he was scouted and recommended to attend two universities: Touto University and Seijo University. After being released from his promise with Saki and realizing that he was still in love with Asahina, he decided to try for acceptance to Seijo University. When he confessed to Suzuka that he wanted to restart their relationship, she stated that she did not because of the fear of getting hurt. Through patience, understanding, and persistence, they made up. During Seijo University's track tryouts, Yamato performed poorly at the start of his race, but showed enough potential at the end for the Selection Committee to unanimously choose him for the scholarship. Pressured by Yasunobu, Yamato decided to take his relationship to the next level. Suzuka initially was against it, but Yamato sets her at ease and they take a step forward in the relationship. Three months later, he learns that Suzuka is pregnant. He is troubled by the decision of her having an abortion and going to the University or keeping the baby and skipping school to work. He admitted to Suzuka that he wants her to keep the baby. After much discussion between the two they both decided to keep the baby and get married, and decided to drop out of the university. They have a daughter named Fuuka.