The way an impundulu was described to me: A vampire/shape shifter/demon that looks like an African supermodel who can seduce women and belongs to a witch, who use him as a sex slave and pass him on to her daughter when she gets too old herself.
An impundulu can turn into either a red/black, red/white or red/black/white bird, which is why I put feathers on his clothes.
How the troll ended up in Africa, I don't know. The idea behind the picture is that he was right in the middle of seducing what he believed to be a normal human woman, when he suddenly noticed that she had a tail. I like to think that she starts following him around and that they eventually fall in love.