Anetoro is the older sister of the main heroine, Hayase Nagatoro, and makes her first appearance in the second season of the anime, Don't Toy with Me, Miss Nagatoro 2nd Attack. Her name is a portmanteau, combining the Japanese word for older sister, ane, with a shortened form of Nagatoro. She is a young woman who shares a strong family resemblance with her younger sister, possessing a similar athletic build and facial features.

In terms of personality, Anetoro is a master of psychological teasing who surpasses even her sister in terms of cunning and sadistic enjoyment. While Nagatoro’s teasing is often impulsive and physically expressive, Anetoro’s approach is more calculated and operates on multiple levels. She finds great amusement in creating awkward and embarrassing situations for others, particularly her sister and Senpai, and she maintains a calm, composed, and cheerful demeanor while doing so. Her teasing can be described as a more refined and devastating form of the family trait, as she uses implication and social pressure rather than direct provocation.

Anetoro’s primary motivation appears to be entertainment derived from observing the romantic tension between her sister and Senpai. She quickly deduces the true nature of their relationship and takes immense pleasure in exploiting it for her own amusement. Her actions are designed to push Nagatoro out of her comfort zone, forcing her to confront her feelings for Senpai, while simultaneously testing Senpai’s character and intentions. Unlike a traditional antagonist, her goal is not to cause harm but to accelerate the relationship’s development through relentless, affectionate meddling.

Within the story, Anetoro serves as a significant catalyst for change and a source of high-stakes comedy. Her role is often to disrupt the status quo, forcing the main characters into situations where they cannot hide from their emotions. When Nagatoro becomes ill and Senpai visits her home to deliver homework, Anetoro is there to orchestrate the encounter, interrogating Senpai and deliberately embarrassing Nagatoro about her unkempt appearance and messy room. She also delights in interrupting intimate moments, such as when she catches Nagatoro feeding pudding to Senpai, and escalates the situation by threatening to show Senpai embarrassing childhood photo albums. Her presence raises the stakes for both protagonists.

Anetoro’s key relationships are primarily with her sister, Hayase Nagatoro, and with Senpai, the male lead. With Nagatoro, Anetoro has a dynamic of a teasing older sister who knows exactly which buttons to push. She treats Nagatoro’s blushing and panicked reactions as the ultimate reward for her schemes. With Senpai, Anetoro is friendly but overwhelmingly intimidating. She uses her authority as an older figure to subject him to a playful but intense interrogation, often joking about calling the police on him for being a potential stalker or pervert, which leaves him flustered and terrified. Despite her teasing, she implicitly approves of him and seems to support the relationship, as evidenced by her efforts to bring them closer together.

As a character introduced in the second season, Anetoro does not undergo significant development herself, but her presence directly influences the development of the lead pair. Her ability is her peerless skill in social and psychological manipulation for comedic effect. She has a talent for reading a room, identifying the most sensitive points in a situation, and applying just the right amount of pressure to cause maximum embarrassment. She achieves this through verbal teasing, well-timed interruptions, and the strategic use of objects like family photo albums, all while maintaining an innocent and cheerful facade.