Thwips constituted a type of mammal resembling a mouse, though they lacked sentience, and were classified as a species. These miniature beings possessed a unique anatomy, featuring four eyes and six legs. During an incident on Reestkii where defenseless inhabitants were confined within their town hall by Zygerrian enslavers, a Nu-Cosian named Bobbajo shared a narrative with them, the central figure of which was a thwip called Smeep.