Nishitani Shizuru

Although the same age, Shizuru moved into town just before the protagonist moved away.
For Shizuru, who has always been shy and had no friends, the protagonist was the first friend she made after moving to town.
She remembers the kindness and wants to be friends with the protagonist again, but her shyness gets in the way, causing her to act tsundere and then regret it.

"By the way, the most hurtful thing was when he said, 'I've never seen Nishitani-san smile before.'"