"Mini-GTS" is a term used in the context of porn videos. It refers to a specific fetish or sexual activity involving the use of small-sized, high-powered vibrators, often with a phallic shape. The "GTS" part of this term likely stands for "Giant (or Great) Titty Stimulator," as these vibrators are typically designed for use on women's breasts and nipples, providing intense stimulation. The term "mini" indicates that the size of the vibrator is smaller than a standard GTS toy, making it more compact and manageable during play. Overall, Mini-GTS is a tag used to describe content featuring the use of small, powerful breast vibrators in sexual activities.