|Hair Color||Light Blond|
|Occupation||Student Council Member|
|Voice Actor||Asami Tano|
Nanao Tachibana is one of Basara's friends who although she is a girl is currently pretending to be a boy. She is part of Hijirigasaka Academy's student council member, as well as being revealed as a Dhampire.
Nanao has a short, small built figure, short blond hair with black hair clips and red eyes behind a pair of Maroon colored glasses. Even though she is a girl her overall features are so petite that she can even undress in front of her classmates and simply be passed off as being an extremely small built boy.
Nanao is shown to be friendly and shy. She has spent a great deal of her life living in fear of herself and the Hero Tribe, to the point that when she found out Basara was a hero she attacked him while professing her innocence in the events surrounding Basara and Ornis. Also she is extremely close to Basara, serving as his gym partner and this attachment intensifies after Basara learns about her Dhampire heritage.
Tachibana is a distant descendant of a famous and murderous Vampire, who even though no one in her family had shown vampiric traits for several generations, Tachibana suffers a form of Atavism that caused her vampiric heritage to manifest. Since then, she has been living in fear of the Hero tribe who have made it their mission to exterminate 'Monsters' like her. The lengths she has gone to to hide, can be seen in the way that she has transferred between several schools and usually disguises herself as a boy.
Nanano is first introduced in Volume IV. Though one of Basara's classmates, she had been unable to participate in the Gym due to her weak physical body and was paired with Basara as his gym partner due to his previous partner Yahiro Takigawa having to suddenly leave. She is part of the student council and is working on the committee for the school festival.
When Basara has a disagreement with one of the older students working on the festival committee over the specialty fireworks the latter had ordered leaves him in a bad spot Tachibana uses her vampiric powers to take over his mind and has him work quietly without causing anymore trouble from now on.
Unfortunately this comes back to bite when this same student is brainwashed into attacking Basara during the sports festival and in the process is made a suspect in the investigation into who had been attacking Basara lately. When the two comes to blows for a short period of time when they learn each other's secret heritages the fighting between them is ultimately ended when Basara renders Nanano unconscious.
Later on the two friends manage to reconcile their differences with minimal difficulty once Nanano's innocence is revealed and Basara reveals that he's not part of the hero tribe anymore.
On the night of the Christmas party for the Student council, Nanano was made to participate in the traditional punishment game/good luck ritual for the school. In her case after randomly selecting her partner, would be method of torture and duration she is undressed and redressed by Basara in the girl's uniform and is still dressed like that until she goes home and changes once the party is over.
- For a long period of time, Nanano's gender has been a source of great debate, initially looking like a girl, she claims to be a boy, but is later on revealed to be a girl after all.