A genuine arousal, sexually, due to flatulence (farting).
When one becomes sexually aroused by a fart which can include on how public it may occur in, at the odour, the sound.
This is considered a sexual fetish, and has given rise to an entire niche, in the adult entertainment industry.
Most Flatulophiles, are males..
Males, more visually stimulated, are the ones who generally are drawn to things they haven't seen or experienced before, accounting for the popularity of this fetish.