Hallo Cel, born October 31, 2006, is a Japanese Vocaloid producer who initially started creating under the alias "eikokoro" on the programming community website Scratch in July 2017. Transitioning to the name "ODD EYE" in 2021, He began sharing Vocaloid works on social media, making an official debut with the release "Dada" on July 31, 2021, which was recognized in the 5th Proseka NEXT music competition. In 2022, after losing contact with a collaborator, he switched from "ODD EYE" to his current moniker. His first release under the new name was "Surprise Dance!" posted on October 31, 2022. Under the "ODD EYE" and later "Hallo Cel" identities, he continued to upload his works on online video platforms, focusing on Vocaloid music. In November 2024, some of his songs began streaming online. A significant milestone was reached on January 5, 2025, when his song "CandyCookieChocolate" surpassed one million views, marking his first major viral success. Shortly after, on January 15, the song also achieved "Hall of Fame" status on the video-sharing site by crossing 100,000 views.