Yuki No Naka Hana: A Flower in the Snow. Just a drabble. FFnet says the story is 106 words, but it lies lol. If it matters, I think this takes place the winter before the series.
Anaru ran shivering into the bus-stop shelter and brushed the snow from her hair and blouse. She started when she recognized Jinta watching her from the bench.
The cold wind nipped Anaru's ankles. She wished Aki hadn't talked her into wearing this outfit. Jinta offered her his coat, holding it awkwardly. Blushing, Anaru sat down beside him. Her pony tail brushed his face as she slipped on his coat.
Jinta said, "The bus is late." Anaru didn't reply but huddled deeper into his coat, pulling her legs up under herself. The snow piled up around them, muting Chichibu in white.