The Blood+ anime, light novel, and manga series features an extensive cast of characters designed by Chizu Hashii and created by Production I.G and Aniplex. The series is set within fictionalized versions of various real-life cities, including Okinawa, Japan; Hanoi,Vietnam; Yekaterinburg, Russia; Paris, France; London, England; Fayetteville, North Carolina; and New York, New York.
The central character of the series is Saya Otonashi, a seemingly ordinary teenage girl who was adopted into the family of Kai and Riku Miyagusuku a year before the series begins and who cannot remember her past. Her life is dramatically changed when she learns that she is a chiropteran—a vampire-like creature—who was born in 1833, survives by drinking the blood of others or receiving it through blood transfusion, and is the only one who can destroy other chiropterans and her twin sister Diva. Saya and Diva are the "queens", the descendants of a line of supremely powerful chiropterans that are always born as twin females. Aiding Saya in this century-long quest is an organization called the Red Shield, with a man named David assigned to be Saya's primary "handler." With Saya forced to return to her former life, she is reunited with Hagi, her chevalier—a special form of chiropteran created by feeding a human the blood of a queen which causes a powerful bond to form and compels the chevalier to serve and protect his queen at all costs.
Characters:
Saya Otonashi
Saya Otonashi was "born" in 1833 from one of two cocoon-like objects taken from the belly of a chiropteran mummy, the other cocoon containing her sister Diva. Both are kept at the "Zoo" by Joel Goldschmidt, where Saya is treated as his daughter and Diva, who is left nameless, is confined to a tower. Saya does not learn about Diva's existence until 1863, when she hears Diva singing and finds her locked in a room at the top of the tower. Saya then names her Diva. In 1870, Amshel purchases a twelve-year-old boy named Hagi from his parents to become Saya's companion and friend.During a birthday party for Joel in 1883, Saya releases Diva so that she can sing for Joel; Diva, however, slaughters everyone in the Goldschmidt house while Saya and Hagi are out looking for Joel's favorite flower.Realizing that Diva is a monster, Saya spends her periods of activity hunting Diva to try to kill her, her chevaliers, and any chiropterans they have created.
Hagi
Hagi is Saya's first, and only living, chevalier. In 1870, he was purchased by Joel and Amshel from his parents for a loaf of bread to be a companion for Saya, with hopes that they might mate and create more specimens for future experimentation. Hagi lives with her in Joel's mansion for many years, him growing up but her never aging. In 1883, he falls from a cliff attempting to pick a flower that Saya wants as a present for Joel's birthday. Misunderstanding an earlier conversation between Hagi and Joel about why Saya lives on blood, and wanting to save him, Saya feeds him some of her blood, unwittingly turning him into a chevalier. Saya feels some guilt over this through the years, but when she apologizes, Hagi assures her that he has no regrets as it allows him to always be at her side while she lives her dream of traveling the world with her sword.