Question: Who is the domestic partner of the painters that made Portrait after a Costume Ball (Portrait of Madame Dietz-Monnin)?
Paraphrase: Who is the household accomplice of the painters that made Representation after a Ensemble Ball (Representation of Madame Dietz-Monnin)?
SPARQL (Wikidata): SELECT ?answer WHERE { wd:Q20268393 wdt:P170 ?X . ?X wdt:P451 ?answer}