Arado is a student of School, which is a DC pilot training program. His class number is Bronzo 28. He's a Sergeant Major.
He's very positive, and always flirts with Seolla, which annoys her. He's part of the Boosted Children, and doesn't have any memories prior to joining The School. He's a very good pilot, though he doesn't get a chance to show off his skills much. They forced him to use mostly long ranged machines, when melee combat is his forte.
He also has a large appetite, and even says that Kusuha's health drink is delicious.