It's Victoria; Zack tells Chloe.

Despite Chloe bouncing on his cock, Zack took to focusing on the slightly open doorway in order to find out who it was. He noticed the feminine shape of the hips, bringing down the list to three girls, the girl had her hand down her open shorts and was furiously getting herself off at the sight of them. Zack felt his cock harden as he moved his eyes up. The girl's other hand was up her shirt and grasping at her medium sized breasts. Zack was certain who it was, but took a look at her face. It was Victoria! Zack's crush (former crush? He thought to himself) was getting herself off on Zack and Chloe's lovemaking scene.

Zack felt himself get harder than ever and Chloe moaned out. It startled Victoria and Zack turned his head back to Chloe in order to make sure she didn't notice him notice her peeking. Zack brought Chloe's head down and said into her ear, “You know we have a somebody watching?”

Chloe moaned, “Fuck, I don't know why, but it's making me hotter. Who is it?”

“It's Victoria.”

Chloe stopped for a second, shocked at the words, but Zack grabbed Chloe's ass and brought it back down on his cock and began to pound back into her, matching her earlier movements.

“Why won't you stop?”

Zack wondered why Chloe was trying to get him to stop, despite wanting this earlier, “Because we can't really stop at this point, and if we did we'd scare off Victoria,” it seemed to put Chloe's mind at ease and she began to move on her own again, but Zack never let go of her ass.

Chloe began to spasm over him for the third time today, and Zack tried to hold himself in, but he couldn't help himself and let some more of his own come fill Chloe even more.

Chloe collapsed onto Zack's body and snuggled into him as she came down off her high. It didn't take long for her to be out like a light despite the sun shining through on them. The hiking and their previous sex had probably tired her out. Zack grabbed the bed sheet and covered up the both of them with it, before taking a look at their now closed door. It seems Victoria had decided to close it for their privacy, despite her violations of it. With the thought of a masturbating Victoria on his mind and the comfort of a now sleeping Chloe at his side, Zack felt himself giving into the tiredness which had come over him.