Maschera: Lament of a Fallen Beast (MASCHERA ～堕天した獣の慟哭～, MASCHERA ~Daten-shita Kemono no Doukoku~) is a fantasy anime series with a dark Gothic theme.
It was broadcast on Thursdays at 5:30 PM, which puts it at the same timeslot as Stardust☆Witch Meruru. The anime series consists of two seasons with 12 episodes per season. It is known that the series have at least two seasons.
On July 1999, a portal to Hell called the Dark Vortex (闇の渦（ダークボルテクス） Yami no Uzu, lit. "Spiral of Darkness") appears in the skies over the city of Tokyo. Within the Kanto Region, various cases of demons opening contracts and creating beings with special powers called "Diablo Ability Users" begin to appear.
The series revolves around Shikkoku, the Dark Hero of the series and his fight against his nemesis, the Queen of Nightmare.
- Shikkoku (漆黒, Shikkoku) - the main protagonist of the series. Shikkoku is a manifestation between a contract between Lucifer and a human named Shinya Kurusu. He wears a black cape and occasionally wears a mask. He is shown to have the ability to summon a three-headed dog.
- Queen of Nightmare (夜魔の女王, Yoma no Jo'oh, lit., "Queen of Night Demons") -the main antagonist of the series. She wears a black dress decorated with roses and crosses.
- Belphegor (ベルフェゴール, Berufuegouru) - a female character.
- Maschera is inspired by the anime series Darker than Black: Ryuusei no Gemini and Code Geass: Lelouch of the Rebellion, among many other series.
- Characters of Maschera look similar to characters in Oreimo. Lucifer and Belphegor have similarities to Kyousuke Kousaka and Manami Tamura respectively.
- The series is written by Kanako Kurusu's older sister Kanata Kurusu.
- Shikkoku is apperantly based of Kanata's friend Shinya Sanada.
- The series is said to be based on Shinya Sanada's school life.
- Kuroneko constantly cosplays as the Queen of Nightmare.