Luna has platinum blonde hair with black tips that reaches her waist. Her eyes are bright red and the left one is usually covered by her bangs. Azusa points out that they look like they are actually glowing.
In her first appearance she wears a black MCR t-shirt, later she cosplays as Misa from Death Note.
Luna seems lighthearted and enthusiastic, and doesn't seem to care much about those who do bad deeds as shown with Masahiko. She likes memes and hamburgers.
Luna used to be a talented artist and got accepted into a prestigious academy, but in a horrible car crash her father died. Her mom couldn't handle being a single parent and grieving her lost spouse, opting for alcohol as a coping method. Luna says she had become insane before she ultimately committed suicide.
In the same car crash that robbed her of her parent, Luna's wrist got injured. Despite her doctor telling her not to draw for six months, she did anyway and thus had to deal with a permanent loss of her drawing ability. Luna fell into depression and could not think of continuing life this way, so she submitted herself to the mental hospital after a few months.
They are so close that in the halloween special, which takes place in an alternate universe where Chiasa and Masahiko aren't in the yakuza, Luna tells Conchita she won't accept her marriage proposal if she stole the ring from some rich person.
- On chapter image 33 there's a small text reading たすけて (most likely 助けて, save me) above her on the chalkboard, though the sentence might as well belong to Shatter next to her.
- Luna and Azusa ship Light with Mikami. Hitomi manages to convince Luna to switch to her side shipping L and Light through a drawing depicting porn of the two