Justin Bieber last edited by
a large intestinal wind that is excreted accidentally when the body is put under extreme pressure to not expel the designated wind. As there is immense pressure prior to wind, follow through is a frequent side effect.
This pressure is due to the host not wanting to expel the wind as they are in a social environment and want to avoid embarrassing name - calling and such.
Usually it is a prolonged muffled sound that is emitted from the pants region of the individual