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Shikkoku
Name in Japanese 漆黒
Romaji Translation Shikkoku
Nickname/s Lucifer

Shinya Kurusu

Debut (Anime) Season 01 Episode 02
Personal Info
Gender Male
Occupation Dark Hero

Shikkoku (漆黒, Shikkokuis the dark hero or the main protagonist of Kuroneko's favorite anime series, Maschera: Lament of a Fallen Beast. Shikkoku is the manifestation of a contract between Lucifer (ルシファーRushifua) and a human named Shinya Kurusu (来栖真夜, Kurusu Shinya). In short the two personalities shares a single body.

Shikkou usually wears a black cape and occasionally wears a mask. He is shown to have the ability to summon a three-headed dog. He became an antagonist halfway in the second season of Maschera. His nemesis is the Queen of Nightmare although a scene Kuroneko and Kyousuke watched suggests that he had romantic relations with the Queen of Nightmare later in the series. 

Lucifer from Maschera Lament of a Fallen Beast about to remove his mask - S01E02 - m18 s45

Lucifer, about to remove his mask

In the Animated Commentary, Lucifer's personality is depicted to be somewhat arrogant, viewing humans as pitiful. However, he is shown to have some sense of humor and is less serious compared to his commentary partner, the Queen of Nightmare. Lucifer remarks that revenge is overrated and boasts that he spends his time eating ramen as a student. Shinya Kurusu barely made an appearance.

Lucifer had an episode of Shinya trying to take over his body during the commentary. He remarked that this happened during the show when he was in school. He concludes that humans were thoughtless as no one tried to help him or showed any concern.

Shikkoku's normal form is shown to be wearing glasses and a uniform consisting of a purple coat, red tie and black pants.

Most probably his real name is based on Shinya Sanada and Kanata Kurusu, the later being the author of the Maschera series. Also, Shikkoku looks similar to Kyousuke and in fact the latter cosplayed as him in one instance in the main series.