There are some interesting descriptions of sex in Brideshead. Waugh avoids any explicit reference to gay sex, but he is slightly more comfortable with marital affairs, taking a quick peek into the bedroom. When Charles returns from his two-year long trip to South America, his reaction to meeting his wife could not be more off-hand if he tried. “There was also a daughter now, she remarked” (218) – noted in the same tone as if she had had the spare bedroom redecorated. When they are at last alone, the scene is described thus:
“She talked in this way while she undressed, with an effort to appear at ease,; then she sat at the dressing table, ran a comb through her hair, and with her bare back towards me, looking at herself in the glass, said “Shall I put my face to bed?”
It was a familiar phrase, one that I did not like; she meant, should she remove her make-up, cover herself with grease, and put her hair in a net.
“No” I said, “not at once”.
Then she knew what was wanted. She had neat, hygienic ways for that too, but there were both relief and triumph in her smile of welcome; later we parted and lay in our twin beds a yard or two distant, smoking”.
Waugh packs a huge amount of information in this brief scene of clinical, hygienic marital sex. When his wife offers herself – obliquely, but quite clearly – to her returning husband after two years apart, she can’t even look at him. She seems to disgust him somewhat – “cover herself with grease”- and his acceptance of her offer is equally half hearted – “not at once”. her relief and triumph derives from his acceptance of her offer. It is later implied that she has been unfaithful in his absence, and that he is aware of this – her relief derives from a mistaken belief that her infidelity has gone unreported, or is forgiven. This is a marriage where little needs to be said – later, when Charles decides to go to see Julia, his mistress, rather than his newly arrived daughter, signalling effectively the end of the marriage, all she says is “I wish it hadn’t got to happen quite this way” (256)

Sex with his mistress on the other hand is more tempestuous, with the storm raging on the Atlantic acting as a usual metaphor:
As we made our halting, laborious way forward…we were alternately jostled together, then strained, nearly sundered, arms and fingers interlocked as I held the rail and Julia clung to me, thrust together again, drawn apart, then in a plunge deeper than the rest, I found myself flung across her, pressing her against the rail, warding myself off her with the arms that held her prisoner on either side” (248)
This plunging and swooping goes on for some time. When the actual, non-metaphorical sex happens a little later, the language Waugh uses is quite extraordinary:
“Julia led me below. It was no time of the sweets of luxury; they would come, in their season, with the swallow and the lime flowers. Now in the rough water there was a formality to be observed, no more. It was as though a deed of conveyance of her narrow loins had been drawn and sealed. I was making my first entry as the freeholder of a property I would enjoy and develop at leisure”. (248)
So not only is this first sexual exchange portrayed in legalistic, commercial terms, but more precisely as a transaction relating to property. Julia eventually inherits Brideshead House, and if they had married Charles would have shared in this inheritance. (Incidentally I wonder if the reference to the “swallow” an accidental punning reference to oral sex? If that’s not too far for you, then this surely is: the mention of lime flowers could be an oblique reference to the fact that lime trees are hermaphroditic, with both male and female parts, suggesting Charles’s tastes are not solely confined to women, as by now we are almost certainly aware.

Portraying sex in novels in the first half of the twentieth century was a challenge – writers were pushing at the boundaries of what public taste and censors would allow, and of course sometimes – Lady Chatterley, Ulysses, The Well of Loneliness, etc – crossing the line. Waugh seems to me to be ambivalent in his references to heterosexual sex – it is treated almost as a necessary evil, but is far from comfortable compared to his treatment of the relationships between men.