A white lion that is known as the jungle emperor. He is very selfless. His son is Leo.

Earth, sometime in the 21st century. Because of non-stop environmental destruction, the United Nations commissions a private company, "Eternal Earth", to create an artificial jungle, to be a nature preserve and to protect animals. All wild animals are forced to live in it. 
The animals that live in this "neo-jungle" have an easy life. Leo, son of Panja, is born in this artificial world. Because of the unrealistic nature of the neo-jungle, Leo lives his life like he hasn't a care in the world. But Leo is ridiculed by the other animals; they call him a coward--he is not like his father, the great Jungle Emperor, but Leo vows that some day he will be. 
Kenichi, son of the Eternal Earth company's CEO, has no doubt about the great success of the neo-jungle. The story starts when Leo and Kenichi meet. Kenichi has the special ability to understand what the animals are saying. 
(Source: kimbawlion.com/2009.htm)

__Height:__ 188cm
__Talent agency:__ LesPros

Mainly known for his roles in Japanese TV drama.

The first 2 minutes of this film are taken from the Jungle Emperor Leo (1965) TV series, while the rest is all original. Tezuka was very pleased that this film conveyed his story accurately, something he wasn't able to do with the TV series.
 
(Source: Anime News Network)

Words from Nagai Go (excerpt from the introduction):
 
The same year as Barbara, Tezuka began serializing Black Jack, and the following year ('74), he introduced Black Jack's assistant Pinoko in the same work, which I think was the prototype for the two characters in Barbara. I think Barbara is a very significant work that marked a turning point in Tezuka's works. I hope you enjoy Barbara: Go Nagai Version, a new interpretation of Barbara in my own way.
 
(Source: Shogakukan, translated)