It's a number code, the same as 69 , only... instead of head to toe, head to head. Can be doggy when the two 6's are facing the same way, or missionary style, when the 6's are facing each other

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.