An amazingly large number of monsters enjoy eating human BRAAAAAAINS!
Ahem, sorry. Brains.
Some times there is a reason for a lust for pink matter: the monster thinks it will get the powers/knowledge/memories of the unfortunate brain owner. Other times... well, maybe brains just taste good.
If there is a brain eater on the scene, expect to see a scooped out head at some point, if for no other [...] [tvtropes.org]