Twilight Maiden
- "Her weird skin color, ability to float in the air with only one wing, and even having a wing at all automatically makes her a monster, NOT a maiden!"
- — Atelier Meruru description
The Twilight Maiden is one of the optional bosses in Atelier Meruru: The Apprentice of Arland.
Although an optional battle, defeating the Twilight Maiden is a key component to the story, and is required to achieve the "Finally, As Planned" and "Witch's Tea Party" endings.
While trying to synthesize the Potion of Youth, Astrid tells Meruru about the Endless Corridor where an ancient demon sleeps. Astrid says that she has once defeated this demon, but now has no ambitions to do so again. Instead, she sends Meruru on a hunt for the Abyssal Soul, a key ingredient in creating the Potion of Youth needed to cure Rorona.
After Astrid reveals the location of the Endless Corridor to Meruru, the player may choose to defeat the Twilight Maiden. Defeating her is worth 100 development points (25 points in Atelier Meruru Plus). After defeating the Twilight Maiden, the much more powerful Void Maiden, Hell Maiden, and Eternity Goddess will appear in her place in the Endless Corridor.