Age Called Blue (Japanese: エイジ・コールド・ブルー, Hepburn: Eiji Koorudo Buruu) is a yaoi manga written and illustrated by est em.

[1] The first three chapters of Age Called Blue were published on the internet by Netcomics prior to the release of the paperback edition.

[2] A poll hosted by Deb Aoki of About.com picked Age Called Blue as its fifteenth most popular yaoi series of 2008,[3] it came second in the following year.

[5] Kinukitty of The Comics Journal praised est em's tale, saying "The relationships feel very real, even if the settings are not strictly plausible.

"[6] David Welsh has called est em's character designs "distinctively real", and praised her characterisations.