Bestiary: cephaloPod
A small parasitic squid that survives by latching onto its victim's skulls and absorbing the host's brain matter through its tentacles. A surprisingly pleasant way to die, thanks largely to the fact that the cephaloPod's feeding habits create a sort of mental backwash which resembles a constant stream of MP3-quality digital audio recordings of the victim's favorite music.
Also available in the more compact gastroPod version.