After inadvertently stumbling upon the princess bathing, Lux, a prince stripped of his title following a rebellion against Arcadia, faces her fury. To settle the score, Lisesharte challenges Lux to a fierce Drag-Ride showdown. These ancient mechanized weapons, unearthed from global ruins, play a vital role in their world. Despite his past as the formidable Drag-Knight, Lux is now dubbed the 'undefeated weakest' due to his vow against attacking. Following the duel, Lux finds himself enrolled in an exclusive academy where royal women hone their skills as Drag-Knights.