Siheyuan: the Perfect Crime? No, Full of Loopholes

[Reasoning + solving crimes + miracle doctor + system + the latest theme of Siheyuan. ] The missing beggar, the odor of corpses, the old Wang who hanged himself in the archives room, the "ghost" seen by the little Sophora japonica... After the original host was discharged from the army, he lived in a courtyard house. After Zhang Xiaonian traveled through time, he found that everything was not that simple. What you have uncovered is just the tip of the iceberg. The sneaky third uncle—— The second uncle who was beaten violently by his two sons—— The old man who peeks at the window all day long—— Everything hints to Zhang Xiaonian, this-siheyuan is not simple!