Inadvertently entering the women's bath of the female dormitory, Lux - a onetime prince of the Arcadia empire, which was overthrown by a rebellion five years prior - has a chance encounter with Lisesharte, the new princess of the realm, catching a glimpse of her in the nude and incurring her wrath as a result. Out of this confrontation emerges a challenge from Lisesharte for Lux to engage in a Drag-Ride battle, employing the use of ancient mechanical armaments excavated from various ruins worldwide. Once deemed the most formidable Drag-Knight, Lux is now regarded as the "undefeated weakest" Drag-Knight, steadfastly refusing to attack during any battle. Following the duel with Lisesharte, Lux finds himself in attendance at a female-exclusive academy that prepares future Drag-Knights for the rigors of combat.