Araragi Nazuna

"I'm glad you came back.
I hope you'll enjoy your summer vacation here."

Ryuusei's old homeroom teacher at Himeshima's elementary school.
She takes Ryuusei in her care when he comes back to the island and is one of the few grown-ups he can rely on.
In the classroom, she's diligent and calm. However, she's also a martial arts master, and she teaches the children self-defense during PE.
All of her former pupils still respect her greatly.