Klismaphilia aka enema / poop fetish is a gay fetish where one derives pleasure from the use of enema. Many gay men who practice klismaphilia claim that they derive sexual pleasure form the beginning to the end of the whole process and not just from the act of the enema being inserted into their rectum.
The sexual pleasure of klismaphilia starts with the feeling of warm enema being inserted into the rectum. Then, the urge to poop that the enema induces creates more pleasure. This pleasure increases as one holds the enema and poop mixture in as the urge to defecate increases. The final climax comes when one can no longer hold in the enema poop mixture in anymore and releases it in one big gush. Many gay men have claimed to cum from the sexual pleasure that they derive from klismaphilia.