When you stick your dick in a woman’s asshole, punch her in the stomach and as her anus clenches you rip your dick out out. You grab her pink sock and begin to play it like a flute. This will result in an instant orgasm as per the legend.
A person who spouts useless nonsense, usually with enthusiasm even though no one cares about the subject. It's like they are playing their poopflute, an instrument they are passionate about, but no one else is.
Did you hear Dave going on about the different types of fruit people should eat for liver detox? That guy is such a poopflute.