If you liked the Bagi, the Monster of Mighty Nature anime, the Anime-Planet community thinks you'd like:
Ikurou is a young man with problems: after a terrible car accident, he was captured by a seedy organization and implanted with a parasite known as Baoh -- a creature which bestows superhuman powers on its host, especially when mortally wounded. While being transported by train, he is accidentally set free by Sumire, young a psychic girl, and the two make their escape. With more of his humanity slipping away by the minute, and the organization hot on their tracks, will the two escape with their lives, or simply cause a bloodbath along the way?
Although Bagi is much more emotional and Baoh is rather action-packed, both movies have the same premise: a monster is being chased because he is considered to be a danger to people, but once you get to know them better you see that they might be more human than their hunters.
Both anime are based on characters created by Tezuka. In both anime, scientists interfere with nature in some way whether it is creating an enviroment (in JEL2009), creating mutants (in Bagi), or cloning (in both). Bagi is a bit darker (though JEL2009 has it's share of dark moments too). Still, if you like one then you might like the other.
Some time ago, Shunsaku Ban witnessed his friend’s murder during a random robbery attempt, and decided to become a guardian for the man’s infant son, Yuno. The child instantly bonded with a mysterious green cat that was carried by the gang, but Shunsaku was convinced that there’s something nefarious about the feline. Now, in the present, his long lost child surfaces in the news as a rich and powerful man who’s having the best luck at the casinos - and somehow, the green cat is still alive and at his side. Determined to save Yuno from the clutches of this evil creature, Shunsaku begins to investigate the truth of what’s really going on...
Both anime were made in the 80's and were both directed by Osamu Tezuka. Also, both anime involve a man who is forced to confront his childhood friend (which in both cases is some sort of cat-like creature). If you like one, you will probably like the other.