Stig is a Sidhe, played by Billy.
Hanging on in quiet desperation is the English way.
Time, Pink Floyd.
Background
It is known that Stig is 32. From this we can extrapolate that he was born in the sixties, and that his parents may well have been hippies.
Mortal Matters
If a mortal met Stig, they would have seen that he is of average height, has short brown hair, and is pleasant without being handsome. His clothes are conservative, and not terribly fashionable. And they would remember little else.
If a mortal occasionally spent time with Stig, they would probably like him, though some may take him for aloof, or a touch too reserved even for an Englishman. Some would see him as a bit of a stiff. However, they would note he is inoffensive and reliable, and appears very capable and efficient.
If a mortal spent quite some time with Stig they may come to notice he has an air about him, equally of absentmindedness, sadness, and wistfulness. His manner and presence is of someone who is not there, who is used to being invisible. Occasionally he seems almost dissociated; he can appear lost in his own world. When engaged in something he becomes involved, almost as if another person animates within him.
Faerie Matters
Stig is a Sidhe of House Eiluned. He is still a fledge, being less than a year since his Chrysalis.
If a kithain met Stig, his physical appearance improves markedly over his mortal form, although he wears it lightly, and is not so grand as many other sidhe affect themselves; although when on occasions he has made the effort he looks the part.
If a kithain spent some time with Stig they may find him seemingly a very un-Sidhe like Sidhe; he does not have the manner or attitude of a distant noble lord. Stig seems unconcerned with that, and perhaps even unaware.
If a kithain spent considerable time with Stig they may have seen moments when he is truly Sidhe; his nature burns out through him. They may have seen Stig demonstrate quite powerful magics (especially for one so recently awakened) on occasion. And they may have seen many more things. Or not.
Stig is constantly attended by Smiley Bone, a chimera. Smiley most often takes the appearance of a pink koosh-koosh ball, and acts much like Woodstock from Snoopy, randomly buzzing around chirriping and meeping. He and Stig seem to get on well, and can communicate. He is a truer extension of Stig than many perhaps realise.