Yagihara is the vocalist and the leader of STAR GENERATION. He is very passionate about the indie music scene and wishes to discover and promote potential musical talents. Yagihara made STAR GENERATION famous in Japan and made many friends in the Japanese indie music scene.
Yagihara is rather wild. His speech may upset people but Tonoya explains that he means well.
After Shikanosuke and Kirari watched STAR GENERATION's performance, Yagihara personally apologized for causing trouble at Taishou earlier that week and praised Shikanosuke's ability at playing tennis.
Chapter 1: Anarchy at the School
Before the Second Literature Club band's performance, Tonoya invited Yagihara to give the band words of encouragement. He revealed that STAR GENERATION debuted at a school festival as well but they failed miserably. Yagihara also watched their performance and recognized Kirari's talent.
Chapter 2: Road to Ruin?
At STAR GENERATION's 5th year anniversary performance, Yagihara delivered flowers from Masayuki to Shikanosuke. At the after-party, Yagihara was sad to hear that the Second Literature Club band is breaking up. He revealed that Kirari has the talent to make it big in the music industry.
Yagihara also explained that playing in a band would not get girlfriends because playing in a band will not provide a stable life that is necessary for a family.
During the summer break, Yagihara phoned Chie and revealed that his friend who owns a live house called Music Farm at Nagoya was interested in having the Second Literature Club band performed at Music Farm's 10th year anniversary. At the after-party, the other bandsmen revealed that Yagihara used to be wilder and he was often criticized for his behavior. STAR GENERATION became more acceptable after Tonoya joined them.
Later, Yagihara explained that he had scheduled the band to play at Osaka.
On Kirari's true ending, STAR GENERATION performed a cover for the Second Literature Club band's first original, 'Let's Jump'. He spontaneously decided to invite Kirari to sing instead. Later, Yagihara announced that he will be starting a record label after the break-up of STAR GENERATION.
Several years later, Kirari released her first original single with Shikanosuke's accompaniment under Yagihara's record label. Yagihara also helped Murakami form his band Happy Cycle Mania.
Kira Kira: Curtain Call
Yagihara invited Murakami to plan the event for Happy Cycle Mania's 5th year anniversary. The event will be held during the Obon festival. Yagihara announced that STAR GENERATION will also be playing during the event. Souta announced that he had reunited Super Rock'n'Rollers and Yagihara invited them to perform as well.