Mackenzie Moss and her BFF Lacy Lennon do everything together. Everything. Brad Sterling, Mackenzie's stepbrother, has really started to wonder how far down the rabbit hole Lacy and Mackenzie have gone. At the same time, he has the total hots for Lacy. Mackenzie notices Brad checking Lacy out beneath the miniskirt of her school uniform. She calls him on it, but doesn't pursue it because the girls decide they need to go shower together. Brad can't believe they possibly do even that together, so he decides to spy on them.

Boy does Brad get an eyeful as he watches Mackenzie and Lacy undress each other. Lacy notices Brad and rats him out, but she can't hide that she returns Brad's interest. Mackenzie is weirded out, but Lacy points out that they do everything together so if Brad wants to look at Lacy he has to look at Mackenzie too. Mackenzie tries to dissuade Lacy by telling her that Brad has a small dick, but that just makes Lacy want to see it. Brad claims his cock isn't small and then whips it out to prove his point. Once Lacy sees how big Brad's dick is, she taunts him while Mackenzie tries to make him go away. The stalemate keeps up until Brad takes Lacy up on her offer and shoves it in.

Mackenzie pretends she's indifferent, but watching Lacy fuck her stepbro is pretty hot. Mackenzie lets Lacy talk her into letting Lacy eat her out while Brad fucks him. Eventually, Mackenzie is too curious about Brad to resist any longer. Lacy is with Mackenzie all the way as Mackenzie scoots forward and lets Brad stick it in. Once she gets started, Mackenzie is eager to see it through as she and Lacy take turns riding Brad's dick. Finally satisfied, the girls work together to deliver a double BJ and handie that only ends when Brad delivers a big shot of cum for the girls to lick clean.