Every night, he sneaks into his futon and his frustrated brother's wife, and his family affair...

I secretly have sex with my frustrated brother's wife in the futon. The heat of intercourse pushes her sweaty breasts against her, and she becomes addicted to her deep pleasure with her sticky slow pistoning. They kill their voices in a dense space just for the two of them, and they repeatedly climax with twitching and climaxing, and inside the futon is filled with intense breaths that hold back from the sticky sound of their genitals rubbing and the squealing. The beast act of hiding in the futon and curtains to prevent his brother from revealing his affair, and ends up being a lewd escarpent...