Kaoru Masaki is a Japanese actor and voice actor born on July 9, 1995, in Saitama Prefecture, Japan. He began his career in the entertainment industry after successfully passing an audition for a game and anime联动 project, which served as his debut.

Masaki is best known for his role as Chizuru Sawamura in the Dream Festival! multimedia franchise. In this project, which spans anime series, music, and live events, he voices the character described as sweet and angelic. His involvement with Dream Festival! extended beyond voice acting, as he was a member of the associated idol group DearDream, performing alongside other cast members. He reprised this role for the second season of the anime, titled Dream Festival! R.

Beyond Dream Festival!, Masaki's voice acting credits include the role of Vaian in the 2020 anime series Saikyou Kamizmode!. He has also taken on live-action roles, such as Jiro Tanaka, a character who transforms into the superhero Rookie, in the series Dogengers. His filmography includes a role in the 2023 movie Henshurei: Deleted.

Throughout his career, Masaki has engaged in recurring collaborations with fellow cast members from the Dream Festival! project. Notably, he shares a friendly rapport with actor and voice actor Masaki Ota, with whom he co-stars. Due to the phonetic similarity of their names, the pair are collectively known as W Masaki or Double Masaki, and they even perform a hand sign forming a W together.