John introduces his best human friend to his best troll friend. Maybe the three of them sit down to watch romcoms, maybe they're just hanging around a lab in the veil, but whatever the circumstance, Dave has trouble paying attention to the conversation at hand. Karkat is good looking and distracting and it's just not fair. Naturally, he begins distracting Karkat while John's talking. Little touches, lip licks, etc. Karkat gets flustered, Dave is thrilled, John is oblivious. It turns into a competition to see who can flirt the most without alerting John to their UST-fueled game.