Shino
The only link to Sawako’s past, Shino was her middle school classmate and the only person who Sawako talks to as the series begins. Shino cares about Sawako and whether she is fitting into high school. She is a cipher, appearing only occasionally as a catalyst for Sawako’s interactions with other people. Perhaps for story reasons, Sawako is too modest to consider her as a friend. Shino was the first to call Sawako by her nickname.