Ruan Xiaowu, nicknamed the Short-Lived Second Brother, is the middle of the three Ruan fishermen in Water Margin. He lives at Shijie Village with Ruan Xiaoer and Ruan Xiaoqi, working poor waters where boats, nets, oars, and knowledge of the reed banks matter more than rank. Wu Yong recruits all three for the robbery of the Birthday Gifts, and Xiaowu helps hide, move, and defend the band after the plan succeeds.
When government officers pursue the seven men, the Ruan brothers draw them into the lake country around the village. From small boats they vanish among channels, call to one another across the water, and attack forces that cannot maneuver in the shallows. This command of local terrain helps the fugitives reach Liangshan. Xiaowu later becomes one of the stronghold’s naval officers, working with Li Jun, Zhang Heng, Zhang Shun, his brothers, and the Tong cousins in ambushes, transport, and attacks from water.
After amnesty he follows the campaigns on rivers and lakes far from Shijie Village. During the war against Fang La, he dies in the fighting around Qingxi after entering the enemy’s inner ground. His best equipment is light: short blade, wet working clothes under simple armor, rope, oar, and low boat. Diving from a deck or rising among reeds expresses him more truthfully than heavy cavalry gear, while the brothers’ coordinated boats preserve the family method that first defeated official pursuit.
