Naoki Ishida, 39, is a member of the idol group Eternal Boys. Before joining the group, he worked as a junior high school teacher but resigned due to personal feelings, later supporting himself through part-time work as a cram school teacher. His personality is driven by perfectionism, leading him to avoid tasks he cannot master and relentlessly pursue error-free performance. This trait fuels his self-description as a "troublesome old man," constantly grappling with a fear of making mistakes against a desire to live without regrets.

His background starkly contrasts with his fellow group members' prior show business experience. Unlike former professional soccer player Haru Asai, presenter Makoto Kakizaki, former child star Tsuyoshi Imagawa, or agency management veteran Daisuke Yamanaka, Naoki entered the idol industry completely without entertainment background. This transition from the education sector to idol performance marked a significant career shift, demanding adaptation to the spotlight's pressures.

As part of Manpuku Entertainment Productions' "mature idol project," Naoki embodies the group's unconventional concept of featuring seasoned professionals instead of typical young idols. Within this framework, he actively contributes to Eternal Boys' goal of proving individuals can pursue new dreams and achieve recognition regardless of age or prior experience.