Miruchi and Yuka are Chiyo's friends from grade school. Despite having skipped ahead into high school, Chiyo still treats them as peers. In both appearance and name, they appear to resemble the girls' teachers, Minamo (Nyamo) and Yukari.
Their first anime appearance was in episode 12 when Chiyo ran into them while walking to school, and in the manga they first appeared when they came to Chiyo's house to go to the movies with her. They both seem to respect Chiyo since she is a high schooler. They are the same height and are fairly friendly with the genius, constantly confusing strangers. An example of this is shown when they go to the movies and they buy grade school tickets while Chiyo buys a high school ticket. They also seem to think a little too highly of high schoolers, believing that high schoolers don't cry, can spend money on food, etcetera. Their second anime appearance was in ep. 20 (which is also in the manga) when they came to show Chiyo their middle school uniforms. Yomi tells them that the school Chiyo goes to has quite a bit of freedom. But then Tomo says "Hey don't look at me."
- In the manga Miruchi was slightly taller, but in the anime there is no noticeable difference in their height.
- The shape of Miruchi's eyes is drawn sharper in the manga, similar to Kagura or Sakaki.
- Miruchi and Yuka were supposedly born in 1989 (around the same time as Chiyo-chan).
- For reasons unknown, Yuka is often referred to as Yuka-chan, while no honorific is used for Miruchi.