Summary:

Shane blinked at Rose. "What," he asked, voice flattening. His fingers twitched against his glass, condensation dripping onto the tablecloth. The words didn't compute. A relationship dynamic sounded like something from a psychology textbook, not whatever chaotic, magnetic pull existed between him and Ilya. "What dynamic? Nothing like that is going on."

Rose’s fingers froze against her glass. She studied Shane’s face. Watching the furrow between his brows, the way his jaw tensed like he was bracing for impact. He genuinely didn’t know. The realization hit her then. “Shane,” she said slowly, “you seriously don’t see it?”

or

Shane realizes that he and Ilya are in a very under negotiated D/s relationship

Google doc of fic chapter 5 starts on page 72!