[tsurezure]

I have a question about the word "pocket monster".
I heard that Nintendo changed the original title "pocket monster" into "Pokemon" because "pocket monster" is a slang for penis.

Unless you work at Nintendo,you don't know the truth.
I want to know that "pocket monster" is really a slang for penis.If so,how frequently is it used?Do you have used it ?Do you have heard someone using the word when refer to penis?
I hope answers from English native speakers.
Thanks in advance.