I translate the first sentence of Faire l'amour: 'I had had someone fill a small bottle of hydrochloric acid, and I kept it with me permanently, with the idea of one day throwing it in someone's face.' Strangely, possessing this bottle has a tranquillising effect on the narrator, who – this was of course written before 9/11 and all subsequent security measures were put in place – even carries it in a suitcase stashed in the hold on a flight to Tokyo with Marie, and escapes with impunity. The narrator is obviously disturbed, the bottle is the source of much of the suspense, and Marie even wonders if the acid will end up being thrown in her face.
Marie is a fashion designer carrying several suitcases of her creations, and she has been enjoying an on-off relationship with the narrator, having wonderful sex and not ceasing to be in love with him, but there's a major problem, and one which Demoulin perceptively pinpoints in one sentence on which the relationship hinges, a sentence which fully explains why this is the last trip the couple will share, why they must part*: 'We loved each other, but we could no longer bear each other. Now, in our love, even if on the whole we were doing ourselves more good than harm, what little harm that we were doing to each other had become unbearable.'
And in the end, the hydrochloric acid doesn't go in Marie's face, in the narrator's own face, or even as a crazy final gesture in the face of the guardian of Contemporary Art Space, but it's poured onto a flower, which may be a violet or a pansy (French pensée means 'thought' or 'pansy'): a final futile, desperate, anguished gesture, or as the narrator puts it, 'an infinitesimal disaster'.
ADDENDUM: Well, in theory at least, but this is of course a post-nouveau roman, so who knows anything?
My other posts on Jean-Philippe Toussaint:
Jean-Philippe Toussaint: Fuir | Running Away
Jean-Philippe Toussaint: Nue
Jean-Philippe Toussaint: La Vérité sur Marie | The Truth about Marie