Schramm.

Lothar Schramm is a simple man with complex problems, yet he seems like such a nice guy. He works as a taxi driver and lives by himself where he is happy to answer his door to strangers and kill them outright. As with many shy loner types he has a problem dealing with women so he drugs them and photographs their nude bodies for sexual stimulation. He then murders his helpless victims and so goes the life of a deranged serial killer.