"Sissy Toy" is a term used in the context of BDSM and gender roleplay, referring to objects or devices used in sexual activities that are meant for humiliation or submission of the person wearing them. Typically, these toys are worn by the submissive partner, who may be dressed in feminine clothing and/or accessories as part of their role play.
Some common examples of sissy toys include chastity belts (devices designed to lock around a man's genitals, preventing him from engaging in sexual activities), cock cages (similar devices that enclose the penis but do not lock), and various types of gags or bit gag. These can be used as part of a dominance and submission dynamic in order to assert control over the submissive partner, and can also serve a humiliating purpose due to their feminine appearance or function.