From Comikey:
Two years after the events of Kengan Ashura, a young man named Narushima Koga aims to enter the Kengan matches, while also seeking out Tokita Ohma for a mysterious reason. He begins to work under Yamashita Kazuo when he meets Gaoh Ryuki, the spitting image of Ohma. Now with a massive showdown between the Kengan Association and Purgatory, another underground martial-arts fighting organization, looming in the background, how will Kouga become strong enough to take part in the legendary Kengan fights?

Official Translations: English, B.Portuguese