Quick synopsis for those unfamiliar with German (paraphrasing liberally):
They met in 1989 at a disco. Love at first sight. Had a son, had a daughter. He was a taxi driver, had his own business. His father was well-to-do, buying him a new car every year. Then she persuaded him to sell his business so that she could get the mother of all boobjobs and become a boob model at 75J (2000cc implants at a cost of 40,000 Euros). They got divorced. The judge allowed him to live in the basement of their mansion.
Long story short, he killed his ex-wife's lover, his ex-wife, his son, then himself. Their daughter was spared.