Ron was pacing in front of the snowy window, twirling his wand in one hand, fingering the Deluminator with the other. Distractedly, he said, "Lumos," and flicked the Deluminator. The tiny light disappeared.
Ron repeated, "Lumos," and his wand lit up again. When he flicked the lighter, the first speck of light flew out and, having nowhere to land, hovered around him.
Curious, he repeated this over and over again, until he was surrounded by a miniature constellation. At the hundredth flick, a ball of light flew out of the Deluminator and disappeared in the centre of Ron's chest.
And suddenly, he knew.