Back Number’s Mutual Love Songs: Popular Song Ranking [2026]

Happy Endingback number15rank/position

back number – Happy End (full)

This song was chosen as the theme for the film “My Tomorrow, Your Yesterday,” which portrays a heartrending love story.

Its poignant, heart‑tightening lyrics and beautiful melody leave a strong impression.

Released in November 2016 as back number’s 16th single, it was written and composed by Iyori Shimizu.

The music video features Tori Matsuzaka and Haruna Kawaguchi, and its delicate depiction of the pain of long-distance relationships and the struggle of parting drew significant attention.

If you’ve experienced a breakup or are troubled about a relationship with someone important, this is a song that will speak to your heart—please give it a listen.

yellowback number16rank/position

back number – Yellow

This is a classic ballad written as the theme song for ABEMA’s romance show “Don’t Be Fooled by the Wolf and the Rainbow,” portraying the bittersweet feelings of unrequited love through metaphors like a “yellow traffic light.” The music video, directed by Yuki Yamato, has become a talking point as a “music video that deepens understanding even without dialogue.” The song’s overall vocal range is D3 to B4, which is somewhat wide and requires skillful use of both chest voice and falsetto, but I think it’s a piece that can be carried more by expressiveness than by pitch accuracy.

If you sing while infusing the lyrics with your feelings and emotions, it will become a thoroughly good performance.

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Kubota Mami

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