Assassination classroom is a show about this creature known as Korosensei, a unknown creature that destroyed about 70% of the moon. Korosensei also wants to destroy the earth a year later but before he does, he wants to teach a class of the middle schoo under achievers. The organization holding him soon allowed him to work at the school and telling the students it is their job to assassinate their teacher within a year to receive a great deal of cash. This, being their only chance to make a name for themselves, they agree and begin trying to murder their teacher while he teaches the students normal everyday subjects.

Anatidaephobia is defined as a pervasive, irrational fear that one is being watched by a duck. The anatidaephobic individual fears that no matter where they are or what they are doing, a duck watches.

Anatidaephobia is derived from the Greek word "anatidae", meaning ducks, geese or swans and "phobos" meaning fear.