Yoasobi
Yoasobi is a Japanese musical duo formed in 2019. It consists of songwriter and producer Ayase and vocalist Lilas Ikuta, under the moniker Ikura. Represented by the slogan "novel into music", the duo's narrative-driven songs are originally based on selected fictional stories posted on Monogatary.com, a social media for creative writing and illustration operated by Sony Music Entertainment Japan. Later, sources also come from various media, such as fiction written by professional authors, books, letters, messages, plays, and social media posts. Known for fast pace and complex structure, their music has been characterized as a blend of J-pop and Vocaloid music.
Rising to prominence during the COVID-19 pandemic in Japan, Yoasobi's debut single, "Yoru ni Kakeru", spent six non-consecutive weeks atop Billboard Japan Hot 100 and topped its 2020 year-end chart, the first ever non-CD single to do so, as well as receiving the first ever diamond and double diamond certifications for streaming figure from the Recording Industry Association of Japan. Three other songs were also certified diamonds: Blue Period-inspired "Gunjō" and anime series openers Beastarss "Kaibutsu" and Oshi no Kos "Idol"; the latter set the record for the longest-running number one on the Japan Hot 100 history with 22 non-consecutive weeks, and the first Japanese act to top the Billboard Global Excl. US, as well as one of the best-selling songs in 2023. With these successes, the duo was dubbed as a representative of J-pop of the 2020s and the Reiwa era.
Yoasobi's first three EPs—The Book, The Book 2, and The Book 3 —explore the "reading CD" theme and peaked at number two on the Oricon Albums Chart. The duo entered the English-language market by translating their songs into English and releasing the EPs E-Side, E-Side 2, and E-Side 3. Furthermore, the duo collaborated with four Naoki Prize-winning novelists—Rio Shimamoto, Mizuki Tsujimura, Miyuki Miyabe, and Eto Mori—to publish the short story collection book Hajimete no, and performed songs based on each story. Yoasobi has received many accolades, including CD Shop Awards, Japan Gold Disc Awards, Japan Record Awards, MTV Video Music Awards Japan, Music Awards Japan, Reiwa Anisong Awards, and Space Shower Music Awards.
Name
The duo's name, Yoasobi, originates from the Japanese word, meaning "nightlife". Ayase, who came up with the name, explained that it is a wish that he and Ikura could take on various playful challenges by comparing their individual career to daytime and Yoasobi's career to nighttime. The duo represents themselves by the slogan "novel into music". With this slogan, if the song they performed is not based on a fictional story, they are not credited under Yoasobi, but separately under their individual names. The official fanclub is called Yoa's, which officially changed from Club Yoasobi in October 2025.History
2019–2021: Formation, "Yoru ni Kakeru" and ''The Book''
Both members of Yoasobi had active music careers before the formation. Ayase was a vocalist of rock band Davinci, which was active from 2012 to 2018 and eventually disbanded in 2020. He began using Vocaloid software Hatsune Miku to produce music during his treatment at hospital due to peptic ulcer disease. He uploaded his first song, titled "Sentensei Assault Girl", on the video-sharing website Niconico in 2018 and gained popularity with "Last Resort" a year later. Then, he released his debut extended play Ghost City Tokyo in December 2019. Lilas Ikuta, who later adopted the stage name Ikura for Yoasobi, is a singer-songwriter and a former member of the cover group Plusonica. She started her music career by performing on the streets and small venues with a guitar at the age of 14, as well as uploading her music and covers on YouTube. In 2016, she participated in a new artist training course, called the Lesson, sponsored by Sony Music Entertainment Japan, and released her demo CD 15 no Omoi. Later, Ikuta released her first two EPs: Rerise and Jukebox through independent label After School.In 2019, Yohei Yashiro, a founder of Monogatary.com, a social media for creative writing and illustration owned by SMEJ, presented the idea of project to produce songs inspired by selected story submissions published on the website as a prize to authors instead of book or anime adaptation, which not all were successful. Yashiro enlisted Shuya Yamamoto, who handled SMEJ's artists at that time, shortly after their first meeting at a party. In the mid-year, Ayase received an offer from Yashiro and Yamamoto to produce songs for the project. During the vocalist discussion, Ayase found Aimyon's "Kimi wa Rock o Kikanai" covered by Ikura on Instagram. He later checked her YouTube channel and contacted her directly to persuade her to form Yoasobi. The duo announced their debut via teaser video on October 1, and marked as their anniversary. The first song by the duo, "Yoru ni Kakeru", was based on the short story Thanatos no Yūwaku written by Mayo Hoshino, which won Sony Music Award at the novel contest Monocon 2019. Its music video was initially uploaded via Ayase's YouTube and Niconico channels on November 16, 2019, which accrued one million views within one month. The song was subsequently released to digital music and streaming platforms the next month, on December 15, independently from SMEJ's label under eponymous personal label and distributed by the Orchard.
Yoasobi was originally planned for making a few songs as a trial run. However, during the beginning of COVID-19 pandemic in Japan in early 2020, "Yoru ni Kakeru" went viral on social media, including The Home Take solo performance by Ikura, bringing it to top several music streaming service charts in Japan. The song first entered the Billboard Japan Hot 100 at number 76 in March, and ascended to number one for the first time in May, five months after its release. The latter spent a total of six weeks atop the chart, of which three weeks were consecutive. The song also topped the Oricon Combined Singles Chart. Eventually, "Yoru ni Kakeru" finished 2020 as the year's number-one Japan Hot 100 song, making it the first-ever single with no physical release to top the year-end chart. The Recording Industry Association of Japan certified the song diamond for exceeding 500 million streams in 2021 and double diamond for 1 billion streams in 2025, becoming the first-ever song in history to achieve these milestones. The song won the Song of the Year at the 2020 MTV Video Music Awards Japan and the 2021 Space Shower Music Awards, and the Silver Prize at the 2023 JASRAC Awards.
Following their debut single, Yoasobi released "Ano Yume o Nazotte" on January 18, 2020. Like "Yoru ni Kakeru", the song is based on another Sony Music Award-winning short story by Sōta Ishiki, Yume no Shizuku to Hoshi no Hana. The next single, "Halzion", sourced from Shunki Hashizume's Soredemo, Happy End, was released on May 11 as part of Suntory's "Immersive Song Project" to advertise energy drink Zone. It was the duo's first collaboration with a professional novelist, whereas the first two were amateur writers. In the second half of the year, they continually released three more singles. The first, "Tabun", was released on July 20 and based on the short story of the same name by Shinano, which won Yoasobi Contest Vol. 1. Used for Bourbon's Alfort Mini Chocolate commercial, "Gunjō", featuring uncredited chorus from Plusonica, was released on September 1. Inspired by the manga series Blue Period, the song was sourced from the short story written by the brand's creative team Ao o Mikata ni. On December 18, the duo released the song "Haruka", a collaboration with screenwriter Osamu Suzuki's short story Tsuki Ōji.
On December 31, Yoasobi concluded 2020 at the year-end television special 71st NHK Kōhaku Uta Gassen with the debut live performance of "Yoru ni Kakeru" as a duo, along with the band members, filmed at Bookshelf Theater, Kadokawa Culture Museum in Tokorozawa. It made the duo the first-ever artist to perform at the TV special without any physical releases. All previously released singles were featured on the duo's debut EP The Book, released on January 6, 2021, expressing a theme of "reading CD" with binder package. It additionally included "Encore", based on Yoasobi Contest Vol. 1-winning Sekai no Owari to, Sayonara no Uta by Kanami Minakami and used for a Google Pixel 5 and Pixel 4a advertisement. The EP debuted at number two on the Oricon Albums Chart and the Billboard Japan Hot Albums. As of 2021, The Book has sold 150,000 CD and 100,000 digital sales, the latter making it the only album to reach the milestone that year, and was certified gold for the both by the RIAJ. The EP won Special Award at the CD Shop Awards.
2021: ''The Book 2'' and English-language releases
First announced in late 2020, Yoasobi recorded both the opening and ending themes for the second season of the Japanese anime series Beastars. Its opening theme, "Kaibutsu", was released on January 6, 2021, the same date as the duo's EP The Book, while its ending theme, "Yasashii Suisei", came on the 20th. Both songs were based on short stories written by the anime's writer Paru Itagaki—Jibun no Mune ni Jibun no Mimi o Oshi Atete and Shishiza Ryūseigun no Mama ni, respectively. Later, the double A-side CD single of both songs was released on March 24. It debuted at number two on the Oricon Singles Chart, and made "Kaibutsu" peaking at number two on the Japan Hot 100. "Kaibutsu" won four awards for Song of the Year in both download and streaming categories at the 36th Japan Gold Disc Award, and ranked number five in Time 10 Best Songs of 2021, the only Japanese act to appear on the list. In support of The Book, the duo held their first livestream concert, Keep Out Theater, on February 14 at the construction site of former Shinjuku Milano-za for 40,000 online audiences. The duo were radio hosts for their All Night Nippon X every Tuesday from March 2021 to 2022.Yoasobi released "Mō Sukoshi Dake" on May 10, using it as the 2021 theme for the morning show Mezamashi TV. It was based on the Yoasobi Contest Vol.3 with Mezamashi TV-winning story Meguru by Chiharu. A song for NTT Docomo's mobile network operator Ahamo commercial, "Sangenshoku", based on scriptwriter Yūichirō Komikado's RGB, was released on July 2. On August 9, Yoasobi released the song "Loveletter" based on Hatsune's letter Ongaku-san e, which won the Letter Song Project, a contest held by Tokyo FM's radio show owned by Japan Post Service, Sunday's Post. Between September 9 and 13, the duo and Sony Park Exhibition held Semiconductors Create New Realities exhibition at Ginza Sony Park, where they first previewed the song "Taishō Roman", based on Natsumi's short story Taishō Romance, which won the Yoasobi Contest Vol.2. The song was released the next two days after the exhibition had finished. The duo was in charge of a theme for Sustainable Development Goals children's television shows Hirogare! Irotoridori, titled "Tsubame", featuring children group Midories. The song was released on October 25, and based on Nana Ototsuki's short story Chiisana Tsubame no Ōkina Yume. In the same month, they published the YouTube Music documentary Yoasobi – Artist Spotlight Stories.
Yoasobi released their second EP, The Book 2, on December 1, 2021. The EP features the duo's all singles released in that year, including "Moshi mo Inochi ga Egaketara", a theme for and based on the 2021 play of the same name written and directed by Osamu Suzuki, performed in August and September 2021. The EP debuted at number two on the Oricon Albums Chart, and topped the Billboard Japan Hot Albums for the first time. It won Special Award at the CD Shop Awards. In support of The Book 2, Yoasobi held their first face-to-face one-off concert, called Nice to Meet You, at Nippon Budokan on December 4 and 5, receiving 14,000 offline attendees, and starred on an episode of documentary program Jōnetsu Tairiku on December 12. The duo participated in the 72nd NHK Kōhaku Uta Gassen on December 31. They performed "Gunjō" for the main show featuring a symphony orchestra, and "Tsubame" as part of "Colorful Special Segment" with Midories and mascots from Hirogare! Irotoridori.
Furthermore, in 2021, Yoasobi began exploring the English-language market by translating the original Japanese song into English, as suggested by the Orchard. The first single, "Into the Night", translated from "Yoru ni Kakeru", was released on July 2. Afterwards, the duo released three more singles: "RGB", "Monster" in July, and "Blue" in October. All songs were included in their debut English-language EP E-Side, released digitally on November 12. Commercially, the EP peaked at number 19 on the Oricon Combined Albums Chart, and number nine on the Billboard Japan Hot Albums. Yoasobi won Artist of the Year at the 2021 MTV Video Music Awards Japan and the 2022 Space Shower Music Awards, as well as the Special Achievement Award at the 63rd Japan Record Awards.