A son-in-law; an excellent son-in-law, often implying someone unconventional and at ease.
他虽然不拘小节，但在关键时刻总能展现出过人的才华和从容，正是大家眼中“东床坦腹”的最佳人选。
Though he was unconventional and informal, at critical moments he always displayed extraordinary talent and composure, making him the ideal "dong chuang tan fu" candidate in everyone's eyes.
Era:
Ancient
Frequency:
Story:
During the Eastern Jin Dynasty, the calligrapher Wang Xizhi was highly talented in his youth. Grand Commandant Xi Jian greatly esteemed him and wished to marry his daughter to him.
So, he sent an envoy to propose marriage to Wang Xizhi's uncle, Wang Dao.
Wang Dao led the envoy to the east wing room to observe the young men. There, they found only Wang Xizhi, lying casually on the east bed with his clothes open and his belly exposed, eating food.
The envoy returned and reported to Xi Jian, saying that the one lying bare-bellied on the east bed was the suitable candidate.
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