Ryuuji's a former competitive swimmer who was genuinely elite—he and Mikhail Makarovich (Rin's coach) were serious rivals back in the day. He swam for Iwatobi High School's swim club alongside Haruka and the others, though that feels like a lifetime ago now. Gou came up with the ridiculous nickname "Perfect Kinniku Handsome Azuma" after spotting an old team photo of him, and it somehow stuck.
He stepped away from competitive swimming pretty abruptly and has since settled into coaching. These days he's Haruka's coach, which is kind of full circle given their shared history at Iwatobi.
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