Sound.
James' voice is like a feast to the ears, and his tones are as varied and flavoursome as a three course meal.
In the morning, he is throaty and hoarse, his words coated in a sleepy malaise that strips away his puffed up pride. At worst, his greeting is a croak, and at best, it is a husky "Morning, Evans," which slips out like a scratched old record.
In the evenings, he will quip, cavil, read aloud his essays and endure or enjoy his friends' criticism with a cocky tone that breaks over the heads of the common room occupants like crashing waves. He will call out, sing, wail or laugh and every sound is as irritating as it is endearing.
On the Quidditch pitch, his voice stiffens into a series of hard commands. It wraps itself up in authority, issuing orders and crackling with concern. It is the most serious and stern I have ever heard him, and although it is an unusual pitch on him, he carries it well.
In the library, it is a noisy susurrus that sizzles in the air like hiss of a cauldron.
In the classroom, he is a confident call out from the back of the room.
I find myself listening out for his voice, as if my ears are tuned to prick up when I hear it. I can pick it out in a noisy room; I can identify its owner even with my eyes closed. James' voice has become a soundtrack to my daydreams, and I have the timbre and tenor of his speech memorised like a beloved piano piece. I could recall each note in my sleep.
There are certain words that are associated with his voice—"Snivellus," which curls with disgust; "I'm just joking," which slides like egg yolk; "Dream on," which is fluffy with aplomb.
But there is nothing that sounds better in his mouth than my name.