|Job||Tsukiyo Kujyō's Doll|
|Manga Debut||Chapter 43|
|Anime Debut||Episode 24|
Luna (ルナ Runa) is Tsukiyo Kujyō's doll. Tsukiyo carries her around wherever she goes, and is almost never seen without her. Luna was the first thing Tsukiyo acknowledged as 'perfect'.
Moon Child Arc
Luna was always with Tsukiyo wherever she went. She was at first Tsukiyo's only interest (other than the moon), but later became less significant in her heart as Keima began his conquest.
Old Conquest Arc
During this arc, it was shown that the goddess Vulcan has used Luna as a vessel of her powers: however, it should be noted that Vulcan resides in Tsukiyo, and Luna was only used as a puppet to scare Keima off.
Tsukiyo trusts Luna as a close friend, and promised her that they would go to the moon someday. Before Keima Katsuragi extracted the spirit from Tsukiyo, Luna was the only perfect person in her eyes. During her arc, Tsukiyo was about the same size as Luna, however when she believed she had shrunk, while looking at a much larger Luna (actually a fake created by Elsie), she shows fear at the sight.
- Luna means "Moon" in Italian and Spanish. It also means "Day of the Moon" in Latin.
- In an Omake, it is revealed that Luna has a grudge against Keima. She drops herself from a high place in order to make revenge against him but fails when she misses. It was later shown that Vulcan was in Luna all along.
- In Roman mythology, Luna is the goddess of the moon and is equated with the Greek Selene. Luna can be used as an astrological name for those born under the sign of Cancer, which is ruled by the moon.