Sex with one of her female relatives

"Well, if I were going to sleep with another girl, I'd want someone I found attractive. Other than you of course," you begin. Lily smiles at your flattery.

"And well, if we're really serious about this, every guy dreams of banging his girlfriend's hot sister. Or her mom, even. Your sisters are really good-looking. And you've said yourself your mom has barely aged a day since she had you," you point out.

You never would have dreamed you would say this out loud to your fiancee, but at the same time, you never dreamed she'd offer you sex with someone else. So you mentally cross your fingers and pray she will bite.