To view destructive sexual behaviors as a form of self-injury is a new concept in the research field that needs further exploration and conceptualization. The aim of this study was to explore experiences of sex as self-injury to identify motives and manifestations of the behavior. An anonymous self-selected open-ended questionnaire was used for the study, and qualitative content analysis was used to identify patterns and themes in the text. A total of 199 informants participated in the study (27.9,  = 9.3 years), all of whom were recruited via a range of websites of Swedish nongovernmental organizations. Sex as self-injury was described as voluntary exposure to sexual situations including psychological and/or physical harm. Affect regulation and receiving positive or negative confirmation emerged as important motives for the behavior. Respondents described sex as self-injury as difficult to stop when it felt compulsive and addictive, with ever-higher risk-taking and self-harming described. Our findings indicate that sex as self-injury often includes deliberate sexual violence, and is similar to other self-injurious behaviors, including non-suicidal self-injury. Sex as self-injury needs to be addressed in healthcare, such as in psychiatry and gynecology departments, to prevent further traumatization.