[2] In reality, Danbo is merely Miura Hasayaka, a friend of the protagonist Yotsuba’s neighbor Ena, inside of a costume made of cardboard.

[3] It was created as a result of a challenge during summer vacation for elementary school students Ena and Miura.

In the second semester, submitted to school as a summer project, Danbo receives a stamp from the teacher on the back of his head that reads "Very well done."

[6] Danbo has also inspired a line of consumer electronics: The Japanese company Planex Communications has introduced a wireless LAN router[7] and a USB hub.

[10] Most surprisingly, the Yotsuba Danbo head is also used as packaging for condoms made by the Japanese brand Okamoto.