No sense in denying it. You've been jerking off to this fantasy for your entire life. Almost every night you've thought about her ass, her bouncy tits, how fucking beautiful your sister is… and now she's actually doing something about it. It wasn't much of a secret, in fact it was pretty blatant. But now it's come to this, a confrontation with you in the hopes it'll get this taboo lust out. Even now in her bikini with your dick in her mouth it's an irresistible feeling. Her reluctance at pleasuring you, sucking you, fucking you it just makes your dick throb harder. But not as hard as watching her moan as you both cheat on your spouse, turning your sister from a hesitant irritated girl into a hardcore brotherfucking slut. So in love with your cock that even talking on the phone to her husband won't slow down her newly awakened love for her sweet big bro. Dreams really do come true.