In addition to Japanese mythology and Taoist and Buddhist symbolism, one of Hell's Paradise: Jigokuraku author Yūji Kaku's biggest inspirations in the making of the series is the 1896 sci-fi horror novel The Island of Doctor Moreau, written by H.G. Wells. The narrative features a protagonist who is left on a mysterious island upon which a mad scientist creates human-animal hybrids through vivisection.