Risa Harada is Riku Harada's twin and Daisuke Niwa's friend and first love. At the start of both the series and manga she rejects Daisuke's confession of love, causing his first transformation into Dark. She falls in love with Dark at first sight and pursues him.
Innocent, spoiled, and depicted as "girly-girl", Risa is often see as the opposite of her twin sister Riku, though both show the same stubbornness and tenacity, particularly when it comes to people they care about.
As the series progresses, Risa's attitude and childish behavior dies down a bit, though she retains her girly nature. She has made several accounts of being more responsible than she was at the beginning of the series. Stated by Riku herself that her sister was just "too nice", example being when they were children. Risa gave up her bunny to Riku who had lost her teddy bear despite loving her bunny a lot. Risa also cares about both Riku and Daisuke, feeling that Daisuke has finally 'got his act together' and sees him in a new light. Risa had made many mature decisions and has shown that, despite her selfishness, she can be just as kind as her twin sister, Riku.
She is initially confused when Riku and Daisuke falls in love, and jealous, but realizes she was more afraid of losing her sister and her friend than wanting Daisuke for herself, and becomes supportive of the relationship.
Riku is her twin sister but has a different personality. Unlike Riku, who is calm, level-headed, and more mature, Risa is energetic, very girly, and somewhat clueless at times. After she rejected Daisuke's love confession Riku falls in love with Daisuke. Despite their differences in personalities and tastes in guys, Riku and Risa are close and care about each other.
In the anime Daisuke has feeling towards Risa that are initially rejected. Risa never really sees Daisuke as "more than a friend," often stating as such indirectly.
Wanting to be with Dark, Risa begins taking great risks to try to see him during his thieving adventures. In the manga Dark initially accepts her affections, then rejects her when he realizes she truly loves him. However, Risa refuses to give him and after noting that she has "become a lady" he agrees to go on a date with her. During the date, she is kidnapped by Argentine who takes her to his world and demands that she, as Dark's "maiden", help him become more like Dark. Dark rescues Risa and progressively has a harder time denying his feelings for Risa.
In the anime adaptation, Risa's crush on Dark appears to die down towards the end of the series due to the fact that Dark had already fallen in love 40 years ago with the twins' grandmother, Rika. Not wanting to tarnish those feelings or end up as a replacement, Risa gradually stopped pursuing Dark as a romantic interest. In the manga, however, this plot does not exist. Her feelings for Dark still remain strong, even when Dark told her that he wasn't human. In chapter 70 Dark told her "I'm always yours alone".
Satoshi is also seen as showing concern for her in the manga, deliberately transforming into Krad — something he normally fights — to try and save her when he sees her falling from a tower during Argentine's attack. Towards the end of the anime, she is shown more frequently with Satoshi, sharing a private glance with him at the end of the series while they avoid looking at Daisuke and Riku embracing nearby.
- At least I'm the cute one!!
- I can't lose to my older sister! Right now she's beating me with 2 meters in chest size!