Emetophilia is a sexual fetish in which an individual is aroused by vomiting or observing others vomit. When emetophiles put emetophilia into practice by actually vomiting, especially on a partner, it is called a Roman shower, after the supposed frequent induction of vomiting at Roman feasts.
For emetophiles, the sequence of "spasm, ejaculation, relief" in vomiting is erotically charged.
An online site theorizes, "vomiting was probably something either arousing or frightening to emetophiles at some point ... it aroused powerful emotions, and the emetophier called upon these emotions for the purpose of sexual gratification." (Frequently Asked Questions about Vomiting)
Emetophilia may be related to emetophobia, the fear of vomiting. Many emetophiles, ironically, continue to fear vomiting themselves despite the amount of time they spend fantasizing about other people vomiting.
In some cases, emetophilia is directly related to vorarephilia. The emetophile fantasizes that he or she is consumed by the person who is vomiting, and imagines him/herself as covered by the contents of the person's stomach while within the stomach of the person who is the target of their fantasy.