Omorashi (Japanese: おもらし / オモラシ / お漏らし, "to wet oneself"), sometimes abbreviated as simply "omo", is a form of fetish subculture first categorized and predominately recognized in Japan, in which a person experiences arousal from the idea or feeling of having a full bladder and potentially wetting themselves, or from witnessing another person in that situation.
While urinary desperation and "wetting" fetishes are not inherently or exclusively Japanese, the clear distinction and definition of "omorashi" as a specific sub-genre of urolagnia media has turned it into a loan-word amongst fetish communities worldwide.
Sub-genres of omorashi include "omorashi yagai" (public urinary desperation or wetting), "omutsu omorashi" (wetting oneself in a diaper), bedwetting, as well as a wide variety of cross-over with other garment fetishes.