The story takes place in warrior kingdom where a deadly martial art called Shadow Skill is practiced to defend the continued existence of the kingdom. Dreaming of becoming an invincible warrior one day, like the legendary warrior named Scar Face who has defeated 2,000 opponents, the boy named Cau Ban trains hard with his older adopted sister Elle who has mastered Shadow Skill. A deadly combat breaks out when a rouge pack of intruders suddenly assaults the castle to steal a box that contains a secret...

Sevalle, an elite breed whose mastery of martial arts has made them legendary. But for the 59th Sevalle, Elle Ragu, a.k.a. Shadow Skill, being a legend is shaping up to be something of a drag. After all, adventure alone doesn't pay the rent, and living check to check takes its toll on even the fiercest warrior. Strong as an ox and stubborn as a mule she may be, but it's drinking like a fish that usually gets Elle in trouble. And as she travels alongside her brother Gau, leaving property damage and unpaid bar-tabs in their wake, a new threat looms on the horizon: spies from the kingdom of Solfan have entered the picture, and Kuruda seems to be headed for war...

In a war-torn world of deadly conflict, one small group of heroes stand against the forces of darkness, armed only with two weapons — their unswerving dedication to good and the superhuman martial art known as the Shadow Skill... For the 14-year-old Gau Ban, it is time once again to return to the grave of his parents, murdered by bandits when he was just ten. In the company of his adoptive sister Elle Lagu, Gau quickly comes to realize that his journey is more than a pilgrimage, and that his combat abilities as a student of the Karuda School of Martial Arts are about to be pushed to the breaking point! Note: The three OVA episodes together (Sevalle, Septia & Sui Rame) are also sometimes referred to as Shadow Skill: The Movie.

In this OVA, the story of Gau's history with his adopted sister and the secrets that make up the shadow skill unfold. The pair make their annual return to the gravesite of Gau's parents, where his growth and progress as a warrior can be exhibited for them. Gau has come along way in his training as a Sevalle under Elle's mentorship, but there are those who wish to find a way of eliminating them, just waiting for the right opportunity to mount a deadly attack. As the travellers make their journey, their family bonds and skill will be tested. Opponents are many, and battles are fierce, but Gau's training also entails taking on his sister in battle, and fully embracing the skills he must learn to defeat his ultimate opponent.