Soul farting is when one stares another in the eyes (soulfully, as it were) and farts. Usually done to insult or catch the latter party by surprise.
"Van peered deeply into Spencer's eyes wistfully, Spencer confused, returned his gaze. After several seconds of this, Van let out a deep, wet sounding fart. The smell was so terrible that Spencer gagged. Needless to say, Spencer was pissed."
Literary example of the Soul Fart