The Butterfly Lovers.

Disguised as a boy to attend school, Zhu Yingtai fell in love with a scholar, Liang Shanbo. The two searched for a way to pursue true love and break the shackles of the conservative world, but their story was destined to end in tragedy. Their love touched the heavens, and they were finally allowed to be together as a pair of butterflies. In this tale, Liang Shanbo was a righteous and kind man. When he fell in love with Zhu Yingtai, he was smitten and vowed to marry only her. However, the Zhu family was vehemently against the marriage, and soon his health gradually deteriorated until he became critically ill. Then, he died and his spirit emerged in the form of a butterfly, just like Zhu Yingtai, so that they could finally be together forever.