He gets caught

Naruto's breath hitched in his throat as the door creaked open slightly. He watched, transfixed by the obscene sight before him. He hadn't even realized he was stroking his own cock through his pants, mirroring Sasuke's motions. His eyes darted back and forth between the two of them, taking in every detail.

Kushina's breasts bounced wildly with each thrust, her nipples dark and erect. Sasuke's muscular back flexed as he hammered into her, and every time he pulled out, a river of their combined juices followed. The room was filled with their grunts and moans, creating a symphony of depravity that only served to fuel Naruto's arousal.

But then, disaster struck. Kushina's hand reached out blindly for something to grab onto and her hand closed around the doorknob. She yanked it open, and there was her son, standing in the doorway with a look of shock and lust plastered across his face.

Sasuke stopped immediately, his cock still buried deep within her. He looked over his shoulder with a smirk, not at all surprised to see Naruto there.

"Well, well, well," he said, his voice low and mocking. "Look what the cat dragged in."