Each character has a distinct personality that makes them a unique addition to the franchise, and fans can see Gaiman's attention to character development. Most characters embody traits inherent to one of the twelve zodiac signs, from the volatile Cain to the logical Lucienne.
Sandman's Dream goes by many names, each of which explains his purpose well. As the Lord of the Dreaming, he controls the unseen realm. He is creative, like many water signs, though he is not as in touch with emotions. Instead, he tries to avoid them.
Pisces rules the twelfth house of dreams, mysteries, and hidden things in astrology. Considering Dream a Pisces feels on the nose. Furthermore, Pisces looks to Neptune, the planet of dreams and prophecies, as its guide. Pisces is a mutable water sign, and like the mutable modality, Dream is adaptable. He has to be after so many years of existence.