Forced masturbation is a form of erotic humiliation commonly used in BDSM and sexual role play practices. The partner that is forced to masturbate is the submissive. The one dictating the masturbation is the dominant.
More About Forced Masturbation
Forced masturbation can be a practice that is used in the bedroom or in public. It can be used as a source of public humiliation. The dominant can dictate all means of masturbation including forcing the submissive into performing degrading masturbatory acts.