Maria is a recurring antagonist in the anime Mermaid Melody Pichi Pichi Pitch. She first appears in episode 6 and is introduced as the last of the Dark Lovers, a group of water demons who serve the main villain, Gaito. Among the Dark Lovers, Maria is the one who holds the closest emotional attachment to Gaito and loves him the most, though she occasionally treats him more like a toy than a romantic partner. She constantly strives to win his favor by doing her best to capture the mermaid princesses, though her attempts usually end in failure.

Maria is a water demon with the ability to control and manipulate ice and snow, which she uses in battle against the mermaid princesses. In appearance, she has long blonde hair and purple eyes. Her personality is generally calm and elegant, but she can also be cold-blooded and cruel when the situation calls for it. Despite her rivalry with the other Dark Lovers, she holds a caring side beneath her surface, especially toward Gaito, and deep down she considers her fellow Dark Lovers to be good friends, even when they argue.

In terms of story role, Maria serves as an obstacle to the main protagonist, Lucia Nanami, and the other mermaid princesses. Her primary motivation is to prove her loyalty and love to Gaito by succeeding in his mission to capture the princesses. She is best friends with two other Dark Lovers, Izuru and Eriru, and is an enemy of Lucia and Hanon. Over the course of the series, Maria does not undergo a major redemption or significant personal development; she remains a faithful servant of Gaito until the end of the conflict. She appears in both the first season and the sequel season, Mermaid Melody Pichi Pichi Pitch Pure.