To create a whistling
noise like that of blowing over a
bottle, except using another person's shit
hole. Thus a shit whistler. Can be used to imply someone is of a homosexual persuasion.
Mike in a childish voice up the stairs: "I've
just turned all the items in your room upside down..."
James runs to his room...
James: "
Ahh mannn! You dirty little shit
whistler!!"