She is so pure, so innocent. It is almost unbelievable.
Hanajima saw Tohru's aurora each time she saw her. It never changed. Never darkened, and it couldn't lighten. She never lost what made her Tohru. Even when she was, unbeknownst to Hanajima, living with in a tent, she never wavered. She stayed the same, glowing with the same innocence, purity, optimistic attitude, and aurora as she always had. She never let the world get her down. She always looked for the good in everything: people, situations, places. Even Hanajima and Arisa.
Tohru's aurora was always white to Hanajima. Pure white.