This porn video tag is a combination of two terms: "spankable" and "boobies."
"Spankable" refers to the act or desire for spanking, often as a form of sexual play or discipline. In this context, it implies that the boobies being described are capable of receiving spanking actions in a sexual manner.
"Boobies" is a slang term for female breasts. It's a colloquial and informal way to refer to this body part, often used within adult or pornographic content.
So, "spankable-boobies" means the desire to spank or be spanked on the female breasts during sexual activities.