Yoasobi is a Japanese pop duo formed in 2019. It consists of musician and record producer Ayase and singer-songwriter Lilas Ikuta, under the moniker Ikura. With the slogan "novel into music", the duo originally released songs based on selected short stories posted on Monogatary.com, a social media website for creative writing operated by Sony Music Entertainment Japan. Sources later also come from various media like stories written by professional authors, books, letters, plays, etc.

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 certification for streaming from the Recording Industry Association of Japan (RIAJ). Besides "Yoru ni Kakeru", three other songs were also certified diamonds: Blue Period-inspired "Gunjō" and opening themes for anime Beastars "Kaibutsu" and Oshi no Ko "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 the 19th best-selling song globally in 2023, according to the International Federation of the Phonographic Industry (IFPI). With these successes, the duo was dubbed as a representative of J-pop of the 2020s.

Yoasobi released three Japanese-language EPs: The Book, The Book 2 (2021), and The Book 3 (2023), which all peaked at number two on the Oricon Albums Chart; and three English-language E-Side (2021), E-Side 2 (2022), and E-Side 3 (2024). Outside their discography, the duo collaborated with four Naoki Prize-winning novelists—Rio Shimamoto, Mizuki Tsujimura, Miyuki Miyabe, and Eto Mori—to publish short story collection Hajimete no in 2022, and performed the songs based on each story. Yoasobi's accolades include multiple CD Shop Awards, Japan Gold Disc Awards, Japan Record Awards, MTV Video Music Awards Japan, Reiwa Anisong Awards, and Space Shower Music Awards.