Sekaiichi HAPPY na Onna no Ko

C-ute-sekaiichi-happy-no-onna-no-ko-regular-cover-3464.jpg from album Dai Nana Shou「Utsukushikutte Gomen Ne」'''

Release September 9, 2011

Genre J-Pop

Format CD Single, CD+DVD, Single V, Event V

Recorded 2011

Label zetima

Producer Tsunku

℃-ute Singles Chronology Previous: Momoiro Sparkling 16th Single

(2011)

Next: Kimi wa Jitensha Watashi wa Densha de Kitaku 18th Single (2012)]] Sekaiichi Happy na Onna no Ko (世界一HAPPYな女の子; World's Happiest Girl) is the seventeenth major label single released by ℃-ute. The single was released on September 7, 2011 and the Single V on September 14, 2011.

The single reached #6 on the Oricon charts and charted for three weeks, selling 19,830 copies, becoming their lowest selling single yet.

Tracklist
thumb|220px|right|Sekaiichi Happy na Onna no Ko (MV)

CD

 * 1) Sekaiichi Happy na Onna no Ko
 * 2) Idai na Chikara wo! (偉大な力を！; Great Power!)
 * 3) Sekaiichi Happy na Onna no ko (Instrumental)

Limited Edition A DVD

 * 1) Sekaiichi Happy na Onna no Ko (Dance Shot Ver.)

Limited Edition B DVD

 * 1) Sekaiichi Happy na Onna no Ko (Color Box Ver.)

Single V

 * 1) Sekaiichi Happy na Onna no Ko (PV)
 * 2) Sekaiichi Happy na Onna no Ko (Close-up Ver.)
 * 3) Making of (メイキング映像)

Event V

 * 1) Sekaiichi HAPPY na Onna no Ko (Yajima Maimi Solo Ver.)
 * 2) Sekaiichi HAPPY na Onna no Ko (Nakajima Saki Solo Ver.)
 * 3) Sekaiichi HAPPY na Onna no Ko (Suzuki Airi Solo Ver.)
 * 4) Sekaiichi HAPPY na Onna no Ko (Okai Chisato Solo Ver.)
 * 5) Sekaiichi HAPPY na Onna no Ko (Hagiwara Mai Solo Ver.)

Featured Members

 * Yajima Maimi
 * Nakajima Saki
 * Suzuki Airi
 * Okai Chisato
 * Hagiwara Mai

Concert Performances

 * 1) Sekaiichi HAPPY na Onna no Ko
 * 2) *Hello! Project 2011 SUMMER ~Nippon no Mirai wa WOW WOW Live~
 * 3) *Hello! Project 2011 SUMMER ~Nippon no Mirai wa YEAH YEAH Live~
 * 4) *Cutie Circuit 2011 ~9gatsu 10ka wa ℃-ute no Hi~
 * 5) *Berryz Koubou & ℃-ute Collaboration Concert Tour 2011 Autumn ~BeriKyuu Island~
 * 6) *Hello! Project ☆ Festival 2011
 * 7) *Hello! Project 2012 WINTER Hello☆Pro Tengoku ~Rock-chan~
 * 8) *Yajima Maimi & Suzuki Airi Acoustic Live at Yokohama BLITZ
 * 9) *℃-ute Concert Tour Spring – Summer 2012 ~Utsukushikutte Gomen ne~
 * 10) *Hello! Project Tanjou 15th Anniversary Live Summer 2012 ~Kitakore Natsu no Fan Matsuri!~ ℃-ute, Fukumura Mizuki, Takeuchi Akari, Katsuta Rina, Kudo Haruka, Ikuta Erina, Sayashi Riho, Suzuki Kanon, Nakanishi Kana, Tamura Meimi, Iikubo Haruna, Ishida Ayumi, Sato Masaki
 * 11) *℃-ute Concert Tour 2012 Winter ~Shinseinaru Pentagram~
 * 12) *Hello! Project Haru no Dai Kansha Hinamatsuri Festival 2013 ~Festival's Eve~
 * 13) Idai na Chikara wo!
 * 14) *Berryz Koubou & ℃-ute Collaboration Concert Tour 2011 Autumn ~BeriKyuu Island~

Song Information

 * 1) Sekaiichi HAPPY na Onna no Ko
 * 2) *Lyrics & Composition: Tsunku
 * 3) *Arrangement, Programming, Guitar, and Bass: Takumi Masanori
 * 4) *Chorus: CHINO & Okai Chisato
 * 5) Idai na Chikawa wo!
 * 6) *Lyrics & Composition: Tsunku
 * 7) *Arrangement, Programming, and Guitar: Fujisawa Yoshiaki
 * 8) *Chorus: CHINO & Tsunku

Oricon Chart Positions
Total Reported Sales: 19,830