"Suction-Dildo" refers to a type of sex toy, typically designed for use by women but can also be used in various other scenarios. It's a dildo that has suction cups on its base which allows it to stick onto different surfaces such as tiles, countertops, etc. This enables the user to have hands-free penetration or engage in self-play while simulating intercourse. The tag suggests that the porn video involves a scene where a character uses a suction dildo for masturbatory or sexual activities.