was a special temporary unit formed by KAT-TUN member Kazuya Kamenashi and NEWS member Tomohisa Yamashita for their 2005 drama Nobuta o Produce. and are the names of the characters Kamenashi and Yamashita play in the drama respectively. Although the drama has long finished on television, the duo have revived their performance of their song numerous times. In 2017, they formed another special temporary unit, , for their 2017 drama Boku, Unmei no Hito desu. "Seishun Amigo" Single information The limited edition consists of three songs and a special 12-page photo booklet, and the regular edition consists three songs and their instrumentals. "Seishun Amigo" was used as the theme song for the drama Nobuta wo Produce starring Kamenashi, Yamashita and Maki Horikita. Musically, the song has a resemblance to Japanese kayōkyoku music of the 1980s. Track list Chart information The unit's sole single "Seishun Amigo" was released on November 2, 2005 and debuted at number one on the Oricon singles weekly chart, selling 520,419 copies. It maintained its number one spot the following week, selling another 250,108 copies. The single sold more than a million copies in less than four weeks and spent a total of sixty-five weeks on the Oricon charts. The single was the best-selling single of 2005 and the third best-selling single of 2006. In 2010, Seishun Amigo was reported by the Oricon's magazine, OriStar, for having sold over 1,627,000 copies and was later certified Million by RIAJ denoting over 1,000,000 shipments. Charts and certifications Charts Sales and certifications Performances 2005.10.23 Utawara Hot Hit 10 2005.10.27 Utaban 2005.10.28 Music Station 2005.10.31 Hey! Hey! Hey! Music Champ 2005.11.04 Music Fighter 2005.11.04 Music Station 2005.11.11 Music Station 2005.11.20 Utawara Hot Top 10 2005.11.30 2005.12.23 Music Station Super Live 2005 2005.12.31 Johnny's Countdown Live 2006.03.18 2006.08.26 2007.12.31 Johnny's Countdown Live 2008.12.31 Johnny's Countdown Live 2009.08.31 24-Hour Television 2009.12.15 Best Artist 2009.12.31 Johnny's Countdown Live 2015.12.31 Johnny's Countdown Live 2017.07.01 The Music Day 2017.12.06 2017 FNS Music Festival "Senaka goshi no Chance" Single information Limited edition 1 consists of one song and its music video and making-of and a special 8-panel lyrics card, limited edition 2 consists of four songs and three instrumentals and a 24-page lyrics booklet, and the regular edition consists of three songs and their instrumentals. "Senaka goshi no Chance" was used as the theme song for the drama Boku, Unmei no Hito desu starring Kamenashi, Yamashita, and