Angela Takatsukasa serves as the subordinate and retainer to Tsubasa Tsubame, heir of the financially struggling Tsubame Tenryu Ryouge martial arts school. Initially hired by Ukyou Sakinomiya to assassinate Yoichi Karasuma, Angela believed the task rightfully belonged to Tsubasa as heir. Observing Tsubasa closely, Angela grew frustrated by her charge's disinterest in assassination and desire for a normal school life.

To force Tsubasa into action, Angela publicly ripped Tsubasa's clothes, triggering a berserk state that enhanced Tsubasa's combat abilities. Their joint attack on Yoichi was interrupted by Ryo Washizu. Deeply wounded when Tsubasa later declared hatred for both martial arts and Angela herself, Angela attempted the assassination alone that night.

During her solo mission at the Ikaruga residence, Angela mistook the Ikaruga sisters for ghosts, unsettling her. She attacked the sleeping Yoichi, but his combat instincts allowed him to evade her strikes. In the struggle, Yoichi inadvertently sexually harassed her before Ibuki Ikaruga and her sisters intervened. After Yoichi awoke, Angela confessed the assassination plot to the Ikaruga family. Yoichi lectured her on using martial arts with pride for her school's revival, not as a mercenary tool.

Following this confrontation, Angela left the dojo and reconciled with the already forgiving Tsubasa. The next day, both began working at a ramen shop, determined to revive their martial arts school through honest labor instead of assassination. Across official media, Angela gradually develops romantic feelings for Yoichi, creating internal conflict as she balances these emotions with her duties to Tsubame Tenryu Ryouge.

Physically, Angela is a 16-year-old girl with a tall, model-like stature and a dynamic physique. Her family name incorporates the kanji for "hawk" (鷹), reflecting her watchful nature over Tsubasa and her weaponized finger talons. Her character evolves from a dutiful assassin into someone seeking redemption through hard work alongside Tsubasa.