1019 is an android (or biodroid) designed by Leon Epstein and sent to escort his sister, Felicia Epstein, to the post-war utopia Oz. Designed in the image of Dr. Epstein's mother but given the body of a man, 1019 has increased speed, stamina, and strength compared to a human being.

~!More recent versions of Epstein MJ3 warn Felicia and Mutou that 1019 is an unstable prototype that will inevitably deteriorate psychologically. Later, this deterioration is revealed to be due to how 1019's brain waves were copied directly from Pamela herself. As time passes, more and more of Pamela's personality takes over 1019, resulting in increased aggresive and cruel behavior.!~

~!1019 escorts Felicia to Oz both as his assigned mission and in the hopes that his creator, Leon, will repair him. Leon makes no such attempt to do so, and the Pamela personality continues to override 1019's own. After aiding in a plan to destroy Oz, 1019 saves the mortally wounded Mutou by cryogenically freezing him before the facility is consumed in an explosion.!~

Loosely based on L.F. Baum's novel, The Wizard of Oz. Original manga done by Itsuki Natsumi. 
A nuclear war has killed most of humanity and split the USA into six warring states. By 2021, a legend has grown up about the fabled city of OZ where everything still works. Scientist Felicia sets out in search of it with the mercenary Muto and android 1019. At the end of the quest they only discover a military base and a madman. 
A mercenary was hired by a girl to bring her to the mythical Oz (a paradise) where her missing brother supposedly lived. Accompanying them was a cyborg sent by her brother. But Oz was not the paradise it seemed and her brother was not as sane as he was smart. 
(Source: AniDB)

1019 Epstein MJ3 Prototype