Pamela, known in the original Japanese version as Hikaru Hiyama, is one of the central characters of the Kimagure Orange Road anime. She is the youngest of the three main figures in the story's love triangle, being two years younger than Kyosuke Kasuga and Madoka Ayukawa, and she shares the same birthday as Kyosuke. An only child who grew up somewhat protected and lonely, she found in Madoka the older sister she had always wanted, and the two became close friends after Madoka retrieved a treasured medallion that a bully had stolen from the younger girl. Her name is associated with the brightness of the sun and a sparkling personality, which suits her role as the most openly cheerful member of the group. Appearance-wise she is a small, youthful girl with light brown hair, and her look reinforces her status as the youngest and most childlike of the leads.

At first glance Hikaru comes across as brash and even aggressive, quick to talk tough and ready to brawl, but this outward boldness gives way to a genuinely kind, sweet, and highly energetic personality once she warms to people. She is candid and direct, expressing her feelings openly and without hypocrisy, and she approaches life in absolute terms: she either loves or hates, with no middle ground. Her childlike side is pronounced. She is immature for her age, prone to tantrums when things do not go her way, and she sometimes slips into a babyish way of speaking when she becomes extremely excited, a habit that signals how sheltered she remains. She also looks up to Madoka and tries to imitate her, though she stays far more openly emotional than her reserved best friend.

Her motivation centers on her love for Kyosuke. She falls for him after witnessing him make an astonishing basketball shot using his psychic power, and from that point she pursues him with complete devotion, addressing him always as "darling." She does not perceive the connection growing between Kyosuke and Madoka, and her trust in both of them remains almost blind even when circumstances suggest otherwise. In the story she functions as the third point of the triangle: Kyosuke dates her while struggling with his true feelings for Madoka, and Madoka hides her own feelings out of loyalty to her friend. Hikaru is therefore both an obstacle to the central romance and a victim of the others' indecision and secrecy, even though it is her own refusal to see what is in front of her that keeps the situation in place.

Her development across the anime involves a slow movement toward maturity. She is aware enough of her own childishness to try to outgrow it, as when she attempts to give up her stuffed animals in the hope of becoming more grown-up, but the deeper change comes as she gradually confronts the reality of the relationship around her. Over the course of the television series, the original video animations, and the later films, her outlook becomes more adult while she retains her warmth and her devotion to the people she loves. Her key relationships define her place in the story. With Kyosuke she is loving and devoted, though his feelings for her remain closer to affection for a younger sister. With Madoka she shares her most important bond, a longtime best friendship rooted in childhood that she treasures as the family she never had. With Yusaku Hino, another childhood friend, she carries an old promise to marry him if he became strong and manly, a pledge that reflects her playful and still very juvenile approach to love.

She has no supernatural abilities, unlike the Kasuga family; her distinctive qualities are her brightness, honesty, and emotional openness, along with a talent for the visual arts that is present in the original story. In the anime, her chief role is that of the spirited, sunny presence whose energy lights up the world around her, standing in quiet contrast to the hesitation and hidden feelings of the other two leads.