Sir Georges Ashton interrupts Mr. Frankland's plans for seduction (Visite nocturne, t3 Michel, 1801) - Marriage after Challiou

The unfortunate Jacinthe goes from family to family to escape the secret of her birth and her persecutors. For a time, she finds refuge in the Frankland family, but she soon falls prey to the advances of Mr. Frankland, who increasingly neglects his wife, despite being Jacinta's friend. One day, when Mr. Frankland declares his love for her, the baronet Sir Georges Ashton, who had also made unsubtle advances on Jacinta in the past, enters the room where they are staying and overhears the scene in progress.

This is what seems to be portrayed in the image, even if it amplifies the situation: there's no mention of pistols or a possible duel in the text, simply the foregrounding of a certain tension between the characters that is soon resolved, except for the poor orphan girl who finds only tormentors wherever she goes.