Appearance:

Jeremiah is a big, powerful-looking man, who doesn’t look like anyone you’d want to meet in a dark alley.  His hair is the same peculiar blue-black shade as his sister Jade’s, and it tends to remind one of a mane.  He usually dresses in dark colors.  His ears are slightly pointed, which sometimes leads people to the false impression that he is elven.

Background:

There was once a tribe of humans that was referred to as “the Wild Ones.” The Wild Ones evidently had a peculiar link to the natural world around them; each person born in the tribe had an affinity for a particular type of animal. This went far beyond “spirit animals” of other tribes. The Wild Ones took on some of the physical characteristics and temperments of the animals. It was also said that the Wild Ones could speak with them. Of course, this is now dismissed as legend and myth, for the tribe of the Wild Ones was lost generations ago.

Jeremiah, like his sister Jade, is one of the last descendants of the Wild Ones.  The bloodlines have of course thinned out, and any characteristics of the Wild Ones appear erratically within the family line, and are not as strong as the original tribe, but they are still there.  (It’s actually very unusual to have two in the family.)  Jeremiah was blind for the first few weeks of his life (again, as was his sister).  This alarmed his parents, and his pointed ears lead to no small confusion.

Jeremiah’s affinity is for wolves.  His sense of smell is nearly unrivaled, and his hearing is excellent.  He’s also very strong, and much faster than you’d think a man of his size would have any right to be.  He can track damn near anything, but he’s never cared much for dogs.  He also tends to be something of a loner.  However, he is fiercely protective of anyone he cares about. 

Jeremiah and his sister Jade are employed by a magician named Reyjen as hunters/bodyguards (positions they excel at).  Most people are smart enough to not pick a fight with Jeremiah (although they usually don’t use the same caution with his sister.)  Reyjen has been the siblings’ friend for years, and once saved their lives.

Roleplaying Notes:

Anyone who spends enough time with Jeremiah and is sufficiently familiar with the stories about the Wild Ones might eventually make the connection.

Jeremiah realizes that he and his sister are oddities, but he doesn’t know much about the legends of the Wild Ones.
Jeremiah’s peculiar nature might attract attention (although it’s much more likely to be his sister that does that), which could be either very good or very bad, depending on the location and culture.

Perhaps the PCs might need the services of a very good hunter and/or tracker.  If they are well-enough known, and know the right people, Jade and Jeremiah might be just the people they want.

Jeremiah is extremely protective about the ones he cares about.  He doesn’t go out of his way to pick fights, but he never shys away from them, either.