I love Yuriko's story; it always makes me cry.
Also, there's a missing page at the first encounter with Yuuya. After Yuriko gave the ball back to Yuuya, she thought Yuuya was extremely cute that she wanted to touch his little face, but she didn't because she felt her hands are dirty (explained in the manga), and she went to wash her hands. Yuuya made a sad face and thought Yuriko didn't like him because of the red marks on his face. That's why he went ahead to explain to her that it's not contagious.