Warning this post talk about fan service, a lot of fan service. There is just so much. Any way, High School of the Dead, is based of the manga by the same name. The manga was written by Daisuke Satō and illustrated by Shōji Satō (who by the way is mainly a hentai artist, which explains a lot about this manga. I looked him up, you know for research reasons). The series first came out in 2006 and ran till 2013. It is currently on hiatus and does not have a date in which it wall be starting again. Along with this anime there is also an OVA that came out in 2011 a year after this anime finished.