Kawahara Touka

Yuu's cousin about the same age. She calls him "Yuu-kun" and always looks up to him.
She suffers from mysterious condition of repeating sudden amnesia - a memory "reset", therefore she always carries around a notebook, where she writes all important memories, so she can remember them after the reset.
She has very bright and cheerful personality, she gets attached to people very easily, almost like a puppy, and she has unique ability to quickly become friends with almost everyone.
She has a speech quirk of starting with "Fumi-", and when she's astonished or dejected, she makes "Gaa-n!" sound effect.