Synopsis: Black Cat Guardian

Maria experienced a traumatic event at the age of ten with the loss of her mother. Currently living alone as a high schooler, she receives a surprise visit from Rufus and Yuri, butlers employed by her previously unknown father. The startling truth is revealed - she is a princess. Overwhelmed by the news, Maria struggles to accept her new identity. However, things escalate when she learns about her father's critical condition and his desire to meet her. Under the guidance of Rufus and Yuri, she begins her training as a princess. Additionally, the series also features a one-shot story called "Kuroneko Guardian."