Wilt: (Wilt Series 1) by Tom Sharpe
Henry Wilt, tied to a daft job and a domineering wife, has just been passed over for promotion yet again. Ahead of him at the Polytechnic stretch years of trying to thump literature into the heads of plasterers, joiners, butchers and the like. And things are no better at home where his massive wife, Eva, is given to boundless and unpredictable fits of enthusiasm - for transcendental meditation, yoga or the trampoline. But if Wilt can do nothing about his job, he realises he can do something about his wife - and as each day passes, his fantasies grow more murderous and more real.