 While it's not impossible that Page took graphic design advice from a demon, it's more likely that he adapted the symbol from Les Dictionaires Infernaux, an encyclopedia of demons written in 1818. However, this book lists the symbol as a protective sigil, not a demonic one. So this means that Evans, a Zeppelin fan, probably took Zozo's name from the symbol he saw in the album and gave it a demonic origin story. Or Zozo just happens to really be into Led Zeppelin.