Dementia 21 Volume 1, which had been published in the digital manga magazine Monthly ComicLoud, is being released as a digital book on June 11, 2011. The works in the book will be the first three episodes of Dementia 21, Kago Mania, and Detective SumoKING, as well as interviews with mangaka Shintaro Kago.

Dementia 21 Volume 1 will be available on the Kindle and the Android. The Kindle edition will be a 166-page bilingual English & Japanese edition, with a price of US$6.99. The Android edition will be a 85-page volume in Monolingual English & Japanese editions, with a price tag of JPY400.