I'm also a big fan of this whole genre. I like the ones that start with the woman being shy and reluctant but end with Black cock "unlocking" her inner slut. I think the emotional component of them, where her anxiety and guilt fades away the deeper into it she gets is a big part of why I like them so much. My wife and I are sort of stuck at the fantasy stage, and I'd love for a dominant, confident Black man to show her what she's missing out on. Most of these fit a three part theme-Reluctant, Seduced, Converted. I think that's why they lend themselves so well to stories-much more satisfying than just pure porn without any context.