As Lilly shows them one of the bedrooms and its connected bathroom, Mona remarks that the bathroom is a little small, so Lilly convinces her to go downstairs to take a look at the bigger bathroom that's there. Once Lilly is alone with Tommy, she comes on to him. Tommy is shocked, and though he protests slightly, Lilly has him in her grasp, removing his wedding ring. They start kissing and touching each other, until Tommy comes to his senses and asks for his wedding ring back.
A few moments later, Tommy regroups with Mona. Lilly cooks up another plan, suggesting they go view an even more impressive bedroom, which also has a connected bathroom. However, when Mona explores the bathroom, Lilly locks her into the toilet area, so Lilly and Tommy can be alone again. Mona says that she can't get out, but Lilly pretends that the door is stuck, and assures her that they will find a way to open it. Her true motive, however, is to seduce Tommy behind Mona's back.
Tommy can't help himself this time and lets Lilly pull out his cock and suck on it. As Lilly does this, Mona bangs on the door and Tommy sends her offhand assurances, trying to buy them time. Eventually, Tommy gets too spooked and has Lilly open the door for Mona. Although Mona is clearly displeased with the door issue, she is none-the-wiser to Tommy and Lilly's adultery.
Lilly then shows them an elevator and convinces Mona to try it, but locks Mona inside and tells her this door is also stuck. Tommy and Lilly then lie to Mona, claiming they will try to find a toolbox, but actually go to the living room to fuck. They have intense, energetic sex - almost forgetting that Mona is alone and waiting to be let out from where she is being kept.