This is Cain Radiance. At the beginning of the story he is 18 years old, but he is now 25 (this drawing is of him when he was 18). He is the prince of the kingdom of Radiance, who was cursed to use an evil sword to save the kingdom from an invasion of monsters. The story begins with him going in search of breaking this curse, looking for Vectorius Razard, a vampire wizard, who may have the answer to what he seeks.

Back Ref: Giaoru