Records of Youth in the Western Jin Dynasty

I don't know who I am? Grandpa said I picked it up, so he said that's it. We run a chicken and feather shop, an inn that provides accommodation for the poor and beggars. They all call me Wa, but in fact, I don't call me Wa. Grandpa called me Li Chengbin, and he called me this name repeatedly. Since I was picked up, how did he know my name? Until one day, a strange customer came to the store, and grandpa disappeared. I wanted to find him, and took the rusty sword in his house with me, and I set out on the road to find grandpa...