| Character Information
Diana (ディアナ Diana) is the third of the Jupiter Sisters. She resides within Tenri Ayukawa and is the first goddess to be revealed.
In sharp contrast to the shy Tenri, Diana is confident and assertive. She is also intelligent and perceptive. But even with her beneficial traits, she also has the capacity to be rather selfish, as most of her actions are for the benefit of Tenri or herself. Given that she is a divine being, she displays a degree of arrogance, presenting herself as being superior to others. However, as the series goes on, she develops into a much warmer person.
With regards to romance, Diana is surprisingly innocent, proven by her frequent attempts to pair Keima with Tenri that have all ended in failure. Her innocence is further displayed by her statement of never having interacted with a man aside from Keima, and seems to hold Tenri's and Keima's kiss with some significance, hinting that her synchronization with Tenri is so strong that she also felt Keima's lips.
Diana's true appearance is never fully shown. A silhouette of her face is shown, however, revealing long, flowing hair. When she possesses Tenri, Tenri's eyes become sharper and her pupils turn red.
Initially, she only possesses a halo. As the series progresses, Diana eventually acquires wings after admitting her romantic affections for Keima.
Whenever she takes control of Tenri's body, Diana shows that she is powerful enough to be able to cut Haqua's hagoromo without difficulty and even hinder an enraged Nora from using a considerably large mace to crush Keima. Diana is also an exceptional strategist — or at the very least a great tactician — supported by the fact that she is a master shogi player, beating experts like Nanaka and Keima with relative ease. It is unknown whether or not Keima lost on purpose, though, as his loss was part of the plan.
In an Omake, Diana tells Tenri that she can also perform magic such as splitting the sea and controlling the weather. Although it is obvious that her magic is ostensibly different from Tenri's tricks.
Despite their contrasting personalities, Tenri and Diana are very close. As a goddess who is currently inhabiting a person, Diana acts as a guardian/older sister to Tenri, protecting her from threats posed by those she deems dangerous. In her quest to make Tenri happy, she tries to do whatever she can, which usually includes either being an audience to Tenri's magic performances or attempting to pair Tenri and Keima together (often ending disastrously).
In the beginning, when Diana was still pretending to be Tenri, she said things that her host lacked the courage to say. The things that she said, however, more often than not mismatched with Tenri's feelings.
Diana is initially hostile towards Keima, despite her attempts to further develop Tenri's relationship with him. However, after Keima proves capable of driving away Nora, she begins to trust him to protect Tenri. She continues to try to push Keima into a relationship with Tenri, her reasons being both to restore her own power and to make Tenri happy. She does not approve of Keima's method of removing runaway spirits, calling him a playboy. Even though Diana has made numerous attempts of forcing Keima to be monogamous with Tenri, she instead develops feelings of her own for him. Realizing her romantic desires toward Keima, she ends up admitting her feelings to him but asks him to love Tenri before she falls in love with him more.
Despite being somewhat similar, Diana and Haqua become entangled in a conflict involving Keima at their very first meeting. While Haqua harbors romantic feelings for Keima — feelings that she is unwilling to admit — Diana desires Keima for Tenri. Haqua's and Diana's initial encounter begins with both of them trying to get Keima away from the other.
Some time after, during the awkward date at the amusement park, the two seem to have become more civil since they ended up viewing Keima as a common enemy. Their compliance shows that they work well together if they are presented with the proper motivation.
Apollo is one of Diana's elder sisters and the two seem to be quite close. Diana shows that she cares for Apollo - and the rest of her sisters for that matter - very deeply when she expresses great worry and frustration when Apollo is stabbed by Fiore.
Due to the frequency of Mars and Apollo fighting with each other, Diana tends to get irritated at them both and tries to get them to stop fighting, illustrating a rare, mother-like demeanor known only by her sisters.
Diana admires Vulcan greatly and shows incredible respect towards her. Out of all of Diana's sisters, she seems to hold Vulcan in the highest regard, seeing as Vulcan is the eldest.
Diana, like how she is with the rest of her sisters, also loves Mars. But because of Mars' attitude and her frequent bickering with Apollo, Diana has her hands full dealing with her.
Diana is shown to be very protective of Minerva, one of the reasons being Minerva's current childlike body. She attempts to protect Minerva's innocence from Apollo's and Mars' teasing.
Mercury's personality makes her difficult to approach. Even her sisters sometimes have a hard time trying to understand her. However, Diana deeply cares for her even though she seems emotionless towards everything. Like Ayumi, Diana seldom refers to Mercury as "Mel".