It’s been scientifically proven that the fewer genes you have for a high melanin count in your skin, the more melanin receptors you have per square mm in your mucosal lining. So when women have sex with dark skinned males the friction causes some of that microscopically to be rubbed off and detected by the receptors in their vaginal mucosal lining, firing off nerve stimulation and giving them more sexual pleasure. It’s basically addictive. Also the melanin receptors react to the melanin content in their sperm and has an even more violent reaction, often bringing them to a climax far greater than what can be achieved otherwise. Happens with white men too if they have sex with a black man