The Mermaid's Forbidden Spell: Mutual Redemption of Atlantis

The deep-sea kingdom of Atlantis is facing a chasm crisis unlike any in a thousand years. They need to arrange a marriage with the Sea Witch clan to use their secret arts to seal the rift; otherwise, the entire royal city will fall into a pitch-black abyss. The crown prince, Samuel, was appointed by his mother, the queen, to marry the Sea Witch princess Morgana when he was young. His adopted brother, Leander, is actually the orphan of the late Sea God general.