Without really intending to, John snorts, amused. "I was not about to shoot you."

What follows is a clean, crisp, above-the-board kiss. John has observed Jem drift in and out of the party, perhaps restless or conversely too tired to be fully present. From this, John supposes what Jems wants is to get this kiss over with: to be a good sport and oblige the game of Jenga, and then be on his way. And John only wants to supply what Jem wants.

He does briefly, gently cup his hand at the back of Jem's head so as not to seem perfunctory. The gesture is also intended to convey a sense of support, or at least acknowledgment that Jem might be feeling exhausted. When he pulls away, he hopes his expression is polite. Nice.

"Just a kiss," he nods.