Toto is Kohza’s father and the only man left living in the deserted city of Yuba. His name is spelled “Tutu” in the 4kids English version of the anime.
Originally, Toto was a relatively fat but healthy looking old man. However due to the three year drought brought about by Crocodile’s scheme, Toto body had completely shriveled up from thirst and starvation to a point that he no longer resembled his former self.

(Source: One Piece Wikia)