You Are Ms. Servant

One day during summer break, Hitoyoshi gets an unexpected visit from a maid at his home. Hitoyoshi is mesmerized by the maid's request to be hired as his maid, but is soon terrified to hear her expertise in assassination, and rejects her offer. However, after being rescued by the maid from nearly getting hit by truck, Hitoyoshi decides to hire her. But that maid was horrible at housework...

Hitoyoshi tries to take in an obedien dog in front of his house as his own. However, the maid cannot get close to the dog because she had a traumatic experience with a dog during her assassin training days. Seeing Hitoyoshi befriend the dog, the maid wishes to join this peaceful and loving world. In hopes of becoming "normal", she asks to be given a name.

Riko, Hitoyoshi's sister, visits the Yokoya family. She's surprised yet intrigued by the maid named "Yuki", the maid's new name. Quickly bonding with Yuki, Riko learns assassination techniques and praises Yuki's unique palate. Together with Hitoyoshi is blown away by the taste of the rice crackers made with her favorite sauce, Katsuta Sauce. Yuki fully enjoys her very first festival.

With Riko's help, Yuki is able to attend the same high school as Hitoyoshi. She joins as "Yuki Yokoya," Hitoyoshi's cousin. As she participates in the scramble for Katsuta bread, she quickly settles into high school life. One day, by Yuki's mistake, Hitoyoshi gets injured and goes to the nurse's office, where he meets Nitta. Yuki feels a sense of danger at the appearance of an alluring woman.

Sensing an assassin's presence in Nitta, Yuki vows to protect Hitoyoshi. She stays glued to him at school and home, day and night. But in a brief moment of distraction, Nitta kidnaps Hitoyoshi and reveales herself as "Grace", an assassin whose target is Yuki—known as "White Wolf Snow (Xuě)," an elite member of "Nine Sons of the Dragon." With Hitoyoshi taken hostage, Yuki's anger peaks.

Grace admits to the overwhelming power of Yuki. "Nitta" will work as a PE teacher on the condition that they won't interfere with each other. Yuki experiences the happiness of living a 'normal' life each day. Meanwhile, witnessing Yuki's emotional reactions to small things, Hitoyoshi becomes more curious about her past and wants to learn more about her.

Shocked to find out that a maid outfit is "not normal," Yuki goes shopping in town together with Hitoyoshi, Riko, and Grace. When she gets home, she notices that the towel cherished by Agemochi-Taro (Mochita) is worn out. When Yuki tries to take the towel for washing, Mochita bares its fangs for the first time. Realizing how important the towel is to Mochita, Yuki...

Yuki is shocked to find out that the popular Katsuta sauce wouldn't be available for another week. At Hitoyoshi's high school, The Great Katsuta Festival is approaching, creating a buzz of excitement. Although the chances of a first-year student winning are slim, Yuki discovers that the prize for winning included Katsuta sauce, which motivates her to strive for victory.

At the Great Katsuta Festival's class competition, Tatsu Hikage, the student council president, posesses excellent combat skills as the successor of the Hikage-style ninjutsu and aims for a third consecutive victory in a "Cops and Robbers" game. Take's younger sister Naka Hikage, also aims to win the competition. Summoning her courage, Naka asks Yuki to be her friend.

Yuki now has a new friend named Naka and is very thrilled. However, Yuki noticed that Hitoshi seems downhearted due to his father's imminent return. Wanting to cheer him up, Snow asks for Riko's help and asks for a date with Hitoshi. Seeing Yuki looking even more beautiful than usual, Hitoyoshi's heart couldn't stop racing, and he started to become aware of his romantic feelings for Yuki.

Hitoyoshi, now aware of his feelings for Yuki, begins to distance himself from her. While Yuki was puzzled by Hitoyoshi’s behavior, she focused on end-of-year cleaning, but her repeated failures brought her to tears. With a heavy heart, Yuki enters the new year and goes on a Hatsumode (New Year's visit to a shrine) with Naka. Snow confides in Naka her fears of Hitoyoshi not wanting her around.

Hitoyoshi's father returns to the Yokoya family household. Seeing his father and Yuki having fun talking about her master, Hitoyoshi feels distant from his father and is unable to exchange words with him. As they are parting, Hitoyoshi finally asks his father the question that had been weighing on his mind. Yuki gives Hitoshi a birthday present.