虞 evokes Emperor Shun's legendary
有虞氏 clan and
虞姬 (Lady Yu) — Xiang Yu's tragic concubine in the
项羽 story, immortalized in the opera 《
霸王别姬》 (Farewell My Concubine). In modern usage, mainly survives in set phrases:
不虞 (unexpectedly),
无虞 (no worries),
尔虞我诈 (mutual deception).