Ep. 4: All Hail Tuba Kun!

4

Kumiko notices the Tuba-kun band-aids on Midori fingers. Midori states that she is enamored by Tuba-kun and has pretty much every merchandise of him, except the capsule toy. When Midori was in middle school, she took her little sister, Kohaku to the park, who naturally wandered off to a handshake greeting while Midori was gone. That's when a Tuba-kun mascot brought back Kohaku to Midori. (Source: Hibike! Euphonium Wiki)