GOODBYE, LARA

Once upon a time, a mermaid princess named Lara fell in love with a human prince. To be with him, she used a witch’s potion to become human—but the magic came at a cost: If she failed to find true love, she would vanish into sea foam forever. Now, 200 years later, Lara awakens in Lake Biwa with one final chance at life and love. (Source: Crunchyroll) — Description from AniList community (anilist.co).