A student in the Male Division at Four Star Academy, he has a bubbly and playful personality. His siblings include younger sister Mahiru Kasumi and older sister Yozora Kasumi, and he has a very thorough understanding of Mahiru's mindset. Member of the idol unit M4 (first male idol unit in the entire Aikatsu! franchise), comprised of the top four students of the Academy's Male Division, with Subaru Yuuki, Nozomu Igarashi and Kanata Kira. Along with Nozomu and Kanata, he teases Subaru about his feelings for Yume on occasion.