Depends on your wife.
What does she do? What does she like for entertainment? Does she follow gossip? TV dramas? Romance novels? Porn? Sex toys? Is she sweet or mean? What makes her tick?
If somebody's really into music, you introduce them to the 2 Live Crew.
If they're really into sports, you talk about how many white girls surrendered to Tiger Woods.
If they follow celebrity gossip then bring up famous white girls who gave in to Big Black Dick.
How direct you can be depends on the person and chance. A new mainstream movie with IR sex scene may come out and get good reviews - go see it together. The idea here is to bring up people enjoying being sexed by Big Black Men.
These are the sorts of things that a Black Pimp would figure out and work with to seduce her.