LIP x LIP is a Japanese virtual idol duo in J-pop and anime song produced by HoneyWorks and signed to Music Ray'n. Active since 2016-12-17, the project is built around the characters Yuujirou and Aizou, also identified as Yūjirō Someya and Aizō Shibasaki, and performed by Kouki Uchiyama and Nobunaga Shimazaki. LIP x LIP was introduced through the Kokuhaku Jikkou Iinkai movie series and made its screen debut on 2016-12-17 with the insert song 「ロメオ」 in 「好きになるその瞬間を。〜告白実行委員会〜」.
The duo made its major debut on 2017-12-6 with the double A-side single "Non-Fantasy (ノンファンタジー)"/"Hitsuyou Fukaketsu", tied to the TV anime "Itsudatte Bokura no Koi wa 10 cm Datta". In that project, "Non-Fantasy (ノンファンタジー)" served as the opening theme and "Hitsuyou Fukaketsu" appeared as an insert song. LIP x LIP released its first major album, 「どっちのkissか、選べよ。」, on 2019-1-16, was the subject of the 2020 film 「LIP×LIP FILM×LIVE〜この世界の楽しみ方〜」, and remained central to the franchise with the 2022 television anime 「ヒロインたるもの!〜嫌われヒロインと内緒のお仕事〜」.
