They're talking about being controlled by entities they're powerless to defend against, and Snart sounds like he's flirting with him. Barry grins despite himself and rolls his eyes.

"Are you ever serious?" he asks, though his gaze does drop to Snart's shoulders, pleasantly muscled beneath his thin black shirt. "It is a nice back, though," Barry adds. "I always wondered what you looked like under that puffy jacket."