Ayumi is a high school student at Maijima Private High School, where she is an active member of the track and field club. She is known for her athletic ability, strong sense of justice, and cheerful nature. Unlike many of Keima’s other conquest targets, Ayumi already knows Keima beforehand, making her conquest somewhat different from those that follow.

In the early part of the series, Keima must win her heart to expel a runaway spirit from within her. Although their relationship starts on rocky terms, Ayumi gradually develops feelings for him, and Keima successfully completes his first capture.

However, during the Goddesses Arc, Ayumi’s significance in the story increases dramatically when she is revealed to be one of the six goddess hosts, carrying Mercury within her. This forces Keima to reconquer her heart, but under far greater emotional and strategic pressure than before.

Ayumi has a slim and athletic build, reflecting her active lifestyle as a runner. She has short, light brown hair, which she often keeps messily tied up, and bright brown eyes that reflect her energetic and competitive nature.

Her typical attire includes the Maijima Private High School uniform, but she is often seen wearing her track and field jersey during practice sessions. Compared to other girls in the series, Ayumi’s tomboyish appearance and casual style make her stand out as one of the more grounded and realistic characters.

Ayumi is outgoing, competitive, and athletic, often displaying a bold and straightforward demeanor. She is quick to speak her mind, unafraid to call out others for their mistakes, especially when it comes to Keima’s strange behavior.

Despite her somewhat hot-headed and easily flustered nature, Ayumi is also caring and supportive, particularly toward her friends and teammates. She has a strong sense of fairness and loyalty, and while she may tease or scold Keima, she eventually grows to trust him deeply.

Her biggest weakness is her insecurity about being a normal girl. She occasionally feels overshadowed by more traditionally feminine girls, worrying that she is too boyish or unappealing. However, Keima’s interactions with her help her overcome this insecurity, showing her that her strength and confidence are what make her truly beautiful.

• The First Capture
  Ayumi is Keima’s first conquest, setting the stage for his journey as a real-life romance expert. Initially, she mocks Keima, finding him weird and disconnected from reality. However, through Keima’s carefully planned strategy, he gradually earns her admiration and affection, leading to her first kiss with him, which successfully expels the runaway spirit from her. Unlike later capture targets, Ayumi already has an established opinion of Keima, making her conquest more personal and dynamic than the others that follow.

• The Goddesses Arc: Mercury’s Awakening
  Ayumi’s role becomes far more significant when she is revealed to be the host of Mercury, one of the six goddesses who can stop Vintage, a rogue faction of demons. To awaken Mercury’s full power, Keima must rekindle Ayumi’s feelings for him, this time in a more emotionally complex and high-stakes situation. However, unlike before, Ayumi’s memories of their past interactions return, making her conquest much harder. She initially distrusts Keima, feeling that he is toying with her emotions. Keima is forced to genuinely earn her love, leading to one of the most heartfelt and difficult conquests in the entire series. During this arc, Ayumi’s character shines, as she proves her unwavering strength by standing up to danger and ultimately accepting her feelings for Keima, allowing Mercury to fully awaken.

• The Final Conquest and Emotional Growth
  By the end of the series, Ayumi remains one of the most important heroines in Keima’s journey. While she does not end up with Keima romantically, she serves as one of the strongest examples of his growth as a person, proving that not all relationships can be treated like a game. Her final interactions with Keima are bittersweet, as she demonstrates her maturity and understanding, showing that she values real emotions over forced romance.