Husband fucks girlfriend behind pregnant wife's back

A man and a woman are on a red leather couch in a kitchen-living area. The woman, in a white lace dress, climbs onto the couch and positions herself for sex while another woman in red stands at the kitchen counter, unaware. The man penetrates her from behind, then switches to missionary and oral positions as she lies back, laughing and relaxed. The scene ends with him continuing to fuck her while she sprawls on the couch beside a laptop.