Personally, I think the husband had her on a dry spell two weeks prior to her being shared. That's why she went crazy for his cock. Hubby wanted to see her being a real slut.
This is an excellent video from a voyeuristic point of view. Obviously, she was doing this to please her husband. I feel bad that she had to sick his Dickson much just to keep him hard because he felt uncomfortable being filmed. Hopefully; you two have transitioned and experienced much more erotic occasions