Choco is a cat-style nurse android. She's quiet, gentle, and does things at her own pace. She speaks slowly. Even when she's angry, she doesn't show it on her face and keeps smiling. She's the type who shows it through her attitude, such as when she injects herself with an extra-large syringe. She's actually quite air-headed.

Choco and Naruto, android sisters with human hearts, were created by a mysterious "Master" as assistants to help in the process of baking "CHOCONARUTO", a pastry that brings happiness. However, their Master has disappeared on a search for true happiness. Choco and Naruto struggle to make the pastry alone, so they embark on a journey to find their Master.