Isaku Senagaki

Age: 15
Birthday: December 20

Isaku Senagaki is the female protagonist of the manga and anime adaptation. She is the granddaughter of a Yakuza Boss and has a crush on her bodyguard, Keiya Uto. To escape her infamous reputation as a Yakuza member and try to live a normal life, she enrolls in Otowa High School, far away from her home.

Isaku is a very beautiful teenage girl who stands at average height with waist length platinum blonde hair, bangs that frame both sides of her face, a fair complexion, full pink lips, and soft purple eyes.

Isaku is noted to be a serious but timid girl. Because she's the granddaughter of a Yakuza boss, Isaku has never had the opportunity to make any friends throughout her childhood, and as a result of this - she doesn't do too well with social interactions. Hence her reclusive nature.

(Source: Ojou to Banken-kun Wiki)