Saya is cosplaying as Maria Kurenai from Vampire Knight. The Vampire Knight manga series and its anime adaption features a relatively small cast of characters created by Matsuri Hino. The series takes place in an alternative future of earth where global warming occurred ten thousand years ago giving rise to immortal vampires and dramatically reducing the number of humans. Their opponents, the vampire hunters were borne of a necessity for humans to defend themselves against the vampires who were turning their kind into the slave army. In spite of being set in future earth, it features a mixture of contemporary and old fashioned technology.
The primary character and heroine of the series is Yuuki Cross, a naive but energetic human, who is the introductory narrator, she is supported by childhood friend and vampire hunter Zero Kiryuu and her crush Kaname Kuran. The story is set in a school environment and originally the cast is divided into human and vampire students, but after the main three characters are eventually revealed to be vampires, the story moves away from the school environment in the second arc. Zero Kiryuu’s revelation as a vampire drives the first half of the first arc and the second half is driven by Yuuki’s revelation to be a vampire. In spite of the secrets held by the two former humans, Kaname is the character with the most secrets, which appear to be the focus of the beginning of the second arc.
While initially developing the characters, Hino reported that though Kaname was created earlier, at every step in the characters' creations, she found it difficult to maintain a balance between Kaname and Zero as she struggled with fears of the former overshadowing the latter.