Slim, awkward and not a little scholarly in general appearance, Calum is a young serpent of average height and marked with a series of diamond-shaped ochre patches surrounded by rings of black and white over his back and head - indicating that he's one of the uncommon but generally ill-reputed viper-kin, not that his diffident and often cautious manner suggests that he's gotten the memo.

 He tends to wear academic robes marked with the sigil of the Erwin Guild (albeit only those of an apprentice) and less often, the hard-wearing working leathers of someone who handles and works with dangerous or aggressive animals - despite which his fingers have the ink-stains of an at least part-time scribe and from time to time, he's got a glowing eldritch sigil on his forehead that looks rather like an Uktena water serpent.

 Come to think of it, that's probably one of the first things people notice.