Like her friends, Della highly cherishes her time within the Light Music Club and later their band Death Devil. She is a highly skilled bassist but does not feel superior to less skilled musicians, seen when she warmly smiled during Yui Hirasawa's apologies for her mistake. As a teenager, she appeared to be unfazed by criticism, seen when she and her friends were scolded by their teacher Horigome.
As an adult, she is willing to play at the wedding of her friend Mihoko without concerns, unlike Sawako Yamanaka who is worried that her past might catch up to her.
Della has shoulder-length light brown hair and grey eyes. As a member of Death Devil, she is seen wearing several different outfits over the years. When visiting Sawako, she wears a light brown winter coat and a checked scarf.
As a teenager, she had much longer hair and usually wore the school outfit of the Sakuragaoka High School.
So far, of all members of Death Devil, only Sawako and Norimi have their real names revealed. Della and Jane are only known under their stage names.
Although she made her real debut in the tenth episode of the second season of the anime, she can already be seen during the fifth episode of the first season. In said episode, she appeared in an image that shows Death Devil while they still visited school, as well as in Sawako's flashbacks.