In a world torn by war, a nation relies on an ancient dragon bound to safeguard its lands. However, these powerful creatures are kept in check by a surprising weakness—their teeth. Enter the dragon dentists, a specialized unit entrusted with the crucial task of maintaining the dragon's oral health. Among the few survivors chosen to join this unique group is Nonoko Kishii, who passed a harrowing test where one must confront their own mortality. Dedicated to their duty, the dragon dentists face an uncertain fate as they diligently care for the dragon's teeth. Their routine is disrupted when Bernard 'Bel' Octavius, a young enemy officer killed and resurrected by the dragon's magic, joins their ranks without undergoing the customary trial. Despite ominous signs surrounding Bel's arrival, Nonoko takes him under her wing as a trainee. Can Bel, a symbol of impending catastrophe, learn to embrace the dragon dentists' acceptance of destiny and aid them in confronting the inevitable challenges ahead?