Well, now there's two distinct versions of her. There's this version, from Prince of Persia, Dark Horizon, then there's the new one from my own project.
Now she's traded the glowing lines on her body for these shadowy marks and the dragon doesn't act as a separate consciousness from her own because her soul isn't split in two. This also means she does actually have negative personality traits, which were separated from her in her original version.
The dragon is the negative side of her, torn out, so she doesn't feel negative emotions, really, or rather, she doesn't express them. Any negative feelings she has are expressed by the dragon, which means her personality is extremely sweet and carefree.
Of course, in her new iteration, she doesn't have that, so that version CAN express negative emotions.