Pen Fifteen, translated to pen15, then translated from leet, means penis. Used by sofisticated nerd everywhere
by SensenmanN December 11, 2005
a trick played on girls who are sweet, oblivious, innocent girls. a mean girl will ask them to join the pen club. she says"i'm pen 13, she's pen 14, and we want you to be pen 15. the girl, oblivious as she is, says ok! then the mean girl writes PEN15 or PENIS on the girl's hand.
by chinchilasrule February 15, 2008