Recorder and RandsellRecorder and Randsell.

Recorder and Randsell (リコーダーとランドセル, Rikōdā to Randoseru; lit. Recorder and Backpack, also known as RecoRan) is a Japanese manga series by Meme Higashiya. It follows the lives of two siblings: Atsushi, a randoseru-wearing grade-schooler with the appearance of an adult, and his elder sister Atsumi, a high school girl with the appearance of a middle-schooler.