"No Doubt" marked Official HIGE DANDism's breakthrough. Released in April 2018, it served as the theme song for Fuji TV's drama Confidence Man JP, becoming the band's major debut single. The song achieved remarkable success in streaming, surpassing 300 million streams in Japan by August 10, 2022, and crossing 400 million streams by June 19, 2024, a clear sign of its enduring appeal. Within Official HIGE DANDism's catalog, "No Doubt" consistently ranks among their most beloved tracks and frequently appears in the top three most requested songs on JOYSOUND karaoke rankings. When Kasane Teto performs "No Doubt", her unique voice - robotic yet expressive, cute yet emotional - would bring a fresh nuance, creating a striking contrast to the original's warm and soulful delivery. Teto's ability to bridge the worlds of J-Pop and the Vocaloid/UTAU community means her version could introduce the song to anime fans, Vocaloid enthusiasts, and net culture followers. Her iconic red twin-drill hairstyle and vibrant personality offer strong visual appeal, making music videos, CD jackets, or performance clips highly shareable and potentially viral. The empowering and confident tone of "No Doubt" would gain new emotional layers through Teto's playful yet sincere interpretation, blending charm with vulnerability. Moreover, the combination of a virtual idol with a hit J-Pop track creates opportunities for cross-media promotion, from rhythm games to virtual concerts and special digital releases. In this way, a Kasane Teto cover could both honor the song's legacy and refresh it for new listeners, amplifying its cultural impact across music and digital media alike.