Marius watches in silence for a moment before it occurs to him to follow Javert's lead, so he hastily pushes himself back to his feet, dusting himself off both as a means to maintain some semblance of being presentable and as an excuse to avoid the other man's eyes.

He gulps upon hearing Javert's voice, and even when he has finished straightening his coat his eyes are still cast to one side. He shifts on his feet once more, tugging nervously at a sleeve. There's a stutter before he manages to say, sincerely enough, "None at all."

Because there is no one he intends to disclose such an intimate dream to; in fact, he would much rather forget the unnerving experience of glimpsing Javert's last moments alive.