Diana

Diana

ディアナ
A Goddess that resides in Tenri, she exhibits characteristics of a tsundere and pure maiden; whenever she is in possession of Tenri's body, there is a halo above her head. She and her sisters—so called "Sisters of Jupiter"—sacrificed themselves to seal the Old Hell. As a "being from the heaven" she requires the power of love to grow, for it is the source of their energy. To obtain more power, Diana asks Keima to marry Tenri.

Later on in the manga it is revealed that she doesn't grow wings because she herself develops feelings for Keima, but in the anime she grew wings after her failed attempt to have Keima kiss her.
(Source: Wikipedia)