The Sibling by Adam Hall
This 1979 novel about sibling rivalry and dysfunctional and dated 1970s attiudes to sex and a screwed up upper middle class family is unreadable and really bad. The useless parents ignore their murderous sexually violent son. People are stupid and this makes your life unpleasant.
“Album of progressive piano classics she'd gotten for him.”
“An adult doing adult things.”
“Seeing a girl in his Jaguar...talking so brightly to Ivan about the influence of Rubinstein on American concert music.”
“They'd always been firing nannies for letting something happen.”
“The smell of the burning Christmas tree still in their lungs.”