Duralumin Bear is a beloved stuffed animal owned by Yotsuba Koiwai in the manga series 'Yotsuba to!' (Yotsuba&!). Although not a living character, Duralumin Bear plays a significant role as Yotsuba’s constant companion, providing her with comfort and emotional support. The bear often appears in scenes where Yotsuba seeks solace or excitement, making it a symbolic representation of her innocence and imagination throughout the series.