Elza is a supporting character in the anime Nyanko Days. She is a Turkish Angora cat who belongs to Azumi Shiratori, a popular and wealthy girl who becomes friends with the shy protagonist Yuuko Konagai.

In terms of appearance, Elza is portrayed as a small, chibi-style cat girl with white fur, blue eyes, and a short neck-length haircut. She is frequently seen with cat ears, a tail, and wears twin tails with hair ribbons, fitting the series aesthetic of anthropomorphic feline characters.

Elza has a distinct and memorable personality. She is described as having a tsundere temperament, acting as a rich young lady with a somewhat bossy and demanding attitude. While she appears chill and relaxed on the surface, she does not like being left alone and can become angry when her owner is late returning home. This is demonstrated in Episode 6, "Azumi and Elza," where Azumi worries about Elza being upset with her for coming home late after spending time with Yuuko at a coffee shop.

Elza's primary role in the story is as the pet and companion of Azumi. Her existence helps to strengthen the bond between Azumi and Yuuko, as their shared love for their cats is a central theme of the narrative. Elza shares a close relationship with Azumi, who takes good care of her. This bond is strong enough that Elza shows signs of jealousy when Azumi begins spending significant time and showing affection towards Yuuko, as Azumi's happiness with her new friend is something Elza has not witnessed before.