Why are you guys so scared to just tell your wife the thought of her fucking another man turns you on? It seems so much simpler and faster than all this other bullshit.. Even if she says no you still planted the seed.. No you can always bring it in conversation especially when she's wet and horny.. Ask her what was the biggest cock she ever fucked, ask her questions until she's telling you about it.. Next time ask her what's the biggest cock she would like to fuck.. Now it's a topic of conversation when you have sex. She'll tell you about all her past lovers.. Then she'll be wanting more...