[quote=@Ontos]
A human living in the labyrinth. Perhaps they have unique skills that monsters can't really do, like smithing nice weapons.
[/quote]

I'd prefer that you roleplay as some sort of monsters, but there may be ways to make a human character work. Keep in mind that the monsters who live in this dungeon have been persecuted by humans, and will be very wary, and maybe even hostile, toward them. You could use a human who has some sort of disease or mutation, for example, that would make them seem monstrous and therefore be outcast from the other humans. Or maybe a human who uses some sort of illusion or disguise to appear as a monster, for whatever reason. That is all that comes to mind for me, but there may be other solutions.