My disclaimer with this is that this character was played for one session. He was 5th or 6th level and I made him to jump in a friend's Curse of the Crimson throne AP.
Grigori Hagson is a Varisian witch. He uses his abilities to serve as a doctor to the poor of Korvosa. He's a jovial (and attractive fellow), despite the fact that his mother is a river hag. His familiar was an ooze bug (something I found in one of the AP's), that could that turned different colors depending on what it ate.
I picked witch abilities specifically for his heritage. He could hold his breath (and sleep underwater), he had claws, and he had the scent ability when tracking children. He was a fun character who's life was cut short due to bad player (and DM) decisions.
One day I'll remake him, start him at 1st level and run with it.