Rio's a first-year at university studying Political Economics while pulling double duty as the keyboardist for Argonavis. He's basically been good at everything since he was a kid—one of those "child prodigy" types—and originally wanted to make it as a baseball player. That dream died pretty quickly though when he got injured right before he could compete in Koushien, so he moved on.
On the surface, Rio comes across as pretty detached. He doesn't show much emotion and keeps people at arm's length, but he made an exception when Yuto recruited him for the band. Since joining up, he's been all in. His family's loaded too—his dad runs one of the biggest confectionery companies down in Hakodate.
Content compiled by AnimeList.moe from publicly available sources.
