Chihiro Isuzugawa, known professionally as Suzu, is a 15-year-old male idol. He stands 168 cm tall, weighs 53 kg, possesses blue hair and blue eyes, and was born on November 16th, making him a Scorpio with blood type A. Despite being the youngest member of Protostar, Chihiro exhibits a notably calm and serene demeanor. He demonstrates reliability and maturity, often assisting other group members with his composed nature. Traits of carefulness and precision align with his blood type A characteristics. He maintains a collected attitude even in challenging situations and rarely becomes flustered. Chihiro hails from the Isuzugawa family, heads of the respected Isuzugawa School of traditional Japanese dance. As the eldest son, he began training under his father, the school's head and his primary instructor, from a very young age. His family fully supports his idol career, with his parents expressing pride in his dual pursuits of dance and music. His younger brother, Mizuki Isuzugawa, actively admires him and is a dedicated fan of Protostar. Before joining Protostar, Chihiro performed as an online singer under the alias "Suzu," showcasing his vocal abilities. His background in Japanese dance significantly contributes to his artistic skills and brings a distinctive cultural element to the group's performances. This training has refined his physical presence, resulting in a slim and stylish physique noted for its grace. Chihiro formed Protostar alongside Akira Kiyose and Banri Naoe after being scouted by talent agency sMiLea Production. During their initial meeting, he displayed curiosity about Banri's habit of wearing masks and sunglasses, attempting to remove them. His family's support and his brother's admiration add personal motivation to his idol activities. The name "Chihiro" combines the kanji for "thousand" (千) and "large" (紘). His surname "Isuzugawa" derives from "fifty" (五十), "bell" (鈴), and "river" (川).