John (, stylized in lowercase) is a Japanese Vocaloid producer and singer-songwriter. As a solo project, he performs under the name Tooboe (, stylized in all caps).
From a young age, John was exposed to guitar and piano and began composing as a hobby using DTM. Around 2018, he discovered artists such as balloon and NayutalieN, which sparked his interest in Vocaloid music. In April 2019, he uploaded his first Vocaloid song, "Inferiority", to Niconico and YouTube, officially beginning his career as a Vocaloid producer.
Since then, he has created notable works such as "Shunran", "Itaino Itaino Tondeike", "Jà Âzai", and "Shinzà Â". "Shunran" has surpassed 45 million views on YouTube.
In September 2020, John launched his solo project under the name Tooboe and began producing both his own vocal works and songs for other artists while continuing his Vocaloid activities. In April 2022, he made his major debut under Mastersix Foundation with his first single, "Shinzà Â".
In 2022, Tooboe performed "Jà Âzai (é å¤)" for the anime Chainsaw Man.
In 2025, Tooboe composed and performed "Anata wa Kaibutsuâ (ãÂÂãªãÂÂãÂÂæªç©; English: You Are My Monster)" as the ending theme for the anime The Summer Hikaru Died (å ÂãÂÂæÂȋÂÂã å¤Â). The anime's official music page notes that the lyrics, composition, and arrangement were all handled by Tooboe. In his comments, he said he delved into the story's themes of memory, betrayal, and what it means to realize someone close is not who you believed, and described the song as a kind of forgiveness extended to the characters. The song was first revealed publicly at AnimeJapan 2025 as part of the main trailer, which featured the ending theme. Other promotional materials and the anime's X / Twitter account also confirmed the non-credit ending video and credited Tooboe as the performer.
The names "John" and "Tooboe" are dog-related, as his musical theme revolves around "underdogs". His primary sources of inspiration for lyrics include "anger" and "giving courage to others." His influences include Hideo Okuda for lyricism and Shikao Suga for composition. A notable characteristic of his Vocaloid tuning is the pronunciation of the kana starting with as , making "tsa, tsi, tsu, tse, tso." As a child, he aspired to become a manga artist.