Elysium no Monogatari

From Blissful Sin:

The Waterfalls of Lowen Petergillian -
They are the waters at the end of the world above. Every river, every lake, every ocean; all water arrives here, Protecting the ends of the world and the city which longs for it, Klinia Roe. On a green hill lies the representation of peace and harmony. The world is ruled by the Higher Prince, Al El. His brother, Serlhon, and an adventurer from the world below begin their journey.
Serlhon admires Ashrei and believes that he is the only one who can free him from monotony. Exactly one year ago, Ashrei and a man-beast, Hephaistos, arrived in this world. Different from the Klinia people and Serlhon, Ashrei Rodd possesses dark hair and eyes of a mysterious light.
During his journey with the strong and manly Ashrei, how will Serlhon grow? What secrets does Ashrei hide?