A coffin draped in chains

Area: Lupanar

Hunt robert the manager at Lupanar. Kill him and get key. After that, go s,e,s. Unlock d, go 3d,e,s,hurl any mobs s till the south door breaks open (you cant picklock or use a key for the door), then just walk into the south room. The coffin will be on the floor. You need to drop any containers/bags you're carry to pick the coffin.