RAL Ω GRAD

During a bloody war, a child is born at the cost of his mother's life. From this baby comes forth a huge and powerful dragon born of shadow that lays waste to the landscape. A quick-thinking knight locks the baby in a cage of darkness, where he grows to be a young man, knowing only the kindness of his young female tutor. Until the day the Shadows attack... (Source: VIZ Media) — Description from AniList community (anilist.co).