Aida is a minor yet notable character in the anime series Higurashi: When They Cry (Higurashi no Naku Koro ni), where she appears during the first season as a classmate and friend of the protagonist, Keiichi Maebara. Though Aida doesn’t take center stage in the overarching plot, her presence plays an important role in shaping the atmosphere and tone of the story, which unfolds in a quiet, rural Japanese village filled with mystery and tension.

In terms of personality, Aida comes across as somewhat shy and reserved, often seen staying close to her friend Houjou Satoko for comfort. She’s easily startled by strange or unsettling events, which only adds to the suspenseful mood that defines the series. That said, despite her timid demeanor, Aida proves herself to be a dependable companion. She regularly joins Keiichi and the others in their after-school activities, showing loyalty and a genuine interest in being part of the group.

Visually, Aida is portrayed with short, dark hair and glasses, dressed in the standard school uniform worn by students at her school. While her screen time may be limited, she contributes meaningfully to the world-building of Higurashi, helping ground the narrative in a sense of realism and everyday life—something that makes the darker elements of the story even more impactful. Because of this, Aida has remained a recognizable and appreciated figure among fans of the franchise.

Now, when we look deeper into Aida’s behavior and mindset throughout the series, there are strong indications that she might align with the ISTJ personality type—Introverted, Sensing, Thinking, Judging. ISTJs are typically practical, organized, and value structure, all of which seem to resonate with Aida’s approach to life and work. As a nurse, she takes her responsibilities seriously, follows protocols meticulously, and maintains a composed, no-nonsense attitude. Her introverted nature is evident in how she tends to keep to herself rather than seek the spotlight.

Moreover, Aida’s attention to detail and preference for order reflect the classic traits of someone who relies on sensory information and logical decision-making. At times, she may come off as distant or overly rigid, especially when enforcing rules—but this isn’t out of malice. Rather, it stems from her belief in consistency and correctness, hallmarks of the ISTJ mindset. Her determination to uncover the truth behind the bizarre incidents in Hinamizawa also highlights her problem-solving drive, another key aspect of this personality type. The fact that she values routine and structured approaches further reinforces the idea that Aida could very well be an ISTJ.

Looking at things from another psychological perspective, Aida also displays characteristics commonly associated with Enneagram Type 1—the Perfectionist. This type is defined by a deep sense of integrity, a commitment to doing what’s right, and a desire to improve themselves and their environment. Aida embodies these qualities through her disciplined work ethic and unwavering moral compass. She holds herself—and others—to high standards, which sometimes leads her to correct people when they deviate from proper procedures.

While this can occasionally create friction, especially with those who are more relaxed or spontaneous, it ultimately comes from a place of principle. Aida isn’t trying to be harsh; she genuinely believes in accountability and justice. In fact, her motivation to expose the truth in Hinamizawa shows just how deeply she cares about fairness and ethical conduct, even if it puts her under personal strain.

So, putting it all together, Aida stands out not because she’s the loudest or most dramatic character, but because of her quiet strength and integrity. Whether viewed through the lens of MBTI or the Enneagram, Aida demonstrates traits consistent with both the ISTJ and Type 1 profiles—reliable, principled, and driven by a need for order and justice. While personality typing isn’t an exact science, and characters (like real people) can show complexity beyond a single label, Aida’s actions and demeanor make a compelling case for these classifications.

Ultimately, Aida may not be the main focus of Higurashi: When They Cry, but her contributions—both to the group dynamic and the overall tone of the series—are far from insignificant. And for many viewers, that’s exactly why Aida remains a quietly memorable part of the story.