Nick: "If we want to smoke and not stink up your dorm, we can shove a dryer sheet inside that cardboard thing and blow the smoke through that"
Jo: "Oh! You mean through a doop de doop?"
Nick: "what the hell are you talking about?"
Jo: "The cardboard thing... It's called a doop de doop"
Nick: "How old are you? Twelve?"
Jo: "We're not friends anymore."
An onomatopoeia for a sound made with the mouth that is usually associated with walking; is a close relative of derdeder but connotates more positive things than its derp cousin. Spongebob coined a similiar phrase when he first stepped on the beach
"I'm going out for a walk doop de doop see ya later"