Although the female classmate didn't hear about how Jian Yiling was treated by the Jian family, she concluded from Mo Shiyun's words that it was Jian Yiling who pushed Jian Yunnao down the stairs.
The female classmate was called Zhu Sha. She was in the same class as Mo Shiyun and Jian Yunnao. Zhu Sha was the representative of the final year experimental class. Her literature grades were exceptional and her other grades were good as well. Although her appearance was average, she had a good relation with Mo Shiyun.
Zhu Sha liked Jian Yunnao. She had previously wanted to get close to Jian Yunnao through Jian Yiling as she was his sister. If she got along with his sister, then her relationship would become closer to Jian Yunnao.
However, Jian Yiling didn't care about her at all. She wasn't even polite about telling her to stop thinking about her brother.