All hail Mashiro!

Wiki copypasta:
Mashiro is a young girl with long dark brown hair and large yellow eyes. The back part of her hair is tied with a white bow. Her hair is sometimes depicted like a tail, straightening and curling depending on her mood.
 
Since she is actually grade school-age, her high school uniform is far too large for her, as shown by her sleeves which cover her hands. She is also smaller than the average 9-year-old, as Kobeni does not believe her when she says that she is 9-years-old at first. It seems that being petite may run in her family, as seen with her mother when The Grim Reaper comes to take her to the afterlife.
 
She has a bit of a bratty personality. But she does love her brother, and the many friends close to her. She will often try to act older than she is, by addressing others, such as Kobeni, very formally.