Lambert can pry Sans's hand off of him, because physical strength has never been the skeleton's forte. That doesn't stop him from instantly teleporting the two of them to the back of the room, however - far enough away to do this without interrupting the ball. This matters to him, right now, based on the Prince's orders.

"Nah, man," he says. "I'm just the messenger."

And then his scorpion tail snakes forward to try to sink its tip into Lambert's knee, as he draws his sword from its sheath.