Itsuki is Aira's 14-year-old younger brother. He's got that annoying little brother energy—constantly teasing her—though he's somehow more mature and way less clumsy than she is. Reina's clearly got a crush on him, which doesn't help the teasing situation.
He's been solid support when it comes to keeping Aira's Prism Shows career under wraps from their dad, working alongside their two younger twin sisters to keep the secret. Beyond that, he seems genuinely interested in carrying on the family business down the line.
What's pretty impressive is that despite his age, Itsuki is already studying to become a sports doctor—a career path that hints at some real ambition and focus for a kid his age.
Content compiled by AnimeList.moe from publicly available sources.
