Sorry if this is stilted. We're having a battle between Sev's native energy and disinclination to be gloomed out and Xel's vibrant sense of paralysis which is probably paralyzing people three states and/or fandoms away. Sev is mostly winning, but it's through a haze of novocain (or actually the opposite, but definitely a haze).
Eta: sorry, coding.
"No, probably not," Severus agrees gloomily. Hating to break it to him, "Well, no doubt it does when you have that face on, but mostly it leaves you looking laid-back."
"Ah." He frowns. "So it doesn't always happen when you're already horizontal."
"You've never done a polar bear," he clarifies, "as opposed to what?"