In December 2005, Peach Pit announced that they were working on a new shōjo manga series called Shugo Chara! The first chapter was published in the February 2006 edition of Nakayoshi magazine and ran until the January 2010 edition. The first volume collection was then republished in July 6, 2006 by Nakayoshi's publisher Kodansha. In addition to the regular volumes, the series is being released in limited editions in Japan, each of which include different cover art from the regular editions, metallic foil sleeves, and a set of postcards featuring Amu in various outfits and poses following the color theme of the dust jackets. Del Rey Manga announced that it acquired the English language rights to Shugo Chara! during MangaNEXT 2006 and released the first volume on March 27, 2007.